I ask how to play the game

I'm certainly aware that there are people who don't play ranked. That's why I said sub level 20 and bronze rather than including unranked and that sort of thing. I'm not sure why you believe that ranked elo has little to do with anything since you seem to be implying normal elo does relate, but the analogy that best fits ranked and normal elo comparison is that ranked is a cash game of poker and normals is a tournament. The variance in normals elo is much higher so it's relevant but harder to use to predict things.

As for the atmosphere issue I would certainly agree that they are very different, but I think it depends on what you find enjoyable. I prefer a more consistent challenge and the process of challenging myself to grow and improve at my hobby. Some people prefer a more relaxed environment. If you read stuff about ranked vs normals you will find out that they have separate mmr scores in an attempt to evenly match people to the best of their ability in very different game circumstances.

Again, I was just making a point that the skill difference between lower level summoners and level 30 is huge, and the skill difference between low elo and even the 50% mark on the ranked ladder is huge, so it doesn't make sense to be upset with lower skill players for being that way. If you don't want to play with them just spam games while actually focusing on playing you best and you won't play w/ people below your skill when you climb. Ta da! Problem solved w/ no need for flaming.

As a side note there is no decay below plat so there isn't any need for you to ever play games to maintain your rank because you won't lose it once you place. I'm not sure if you're consistent in your effort in normals or if you play a lot of stuff you don't know well/roles to practice them, but it sounds like you're an upper silver player if you play consistent and maybe a low gold player if you're playing inconsistent in normals so you should never have a problem placing somewhere in silver every season w/ only the 10 placement games if that's all you want to play in ranked. I just thought I'd throw that in for you if you don't like ranked bc I can definitely understand since I'm not really a fan of normals due to the higher variance.

Ranked elo has everything to do. People don't try in normals.

I can see where you're coming from, but I would argue you misinterpret my post or haven't accurately extrapolated the implications of the underlying concept (although I may just be wrong and we simply disagree about the concept I was expressing). First let me say that yes, I believe a significant rank gap does indicate a higher maximum overall or specific skill level. However, the post I made clearly states that because of this assumption I believe people should be more polite and helpful to lower rank/level players who may be/are weaker players (obviously with level there is greater variance because not all low level players are playing for the first time, or would be a low rank even if they are, my best friend would crush me even as a level 15 probably bc by then he would have learned the game and he is stronger than me at every game we have ever played so my guess is he'd be around low/mid diamond level if he picked up lol seriously, maybe D1). Imo, a much larger issue w/ the community are the two groups of people who either believe rank is an absolute measure (there is a lot of overlap between Silver I and Gold V skill, and some players have great macro play, or utility, but terrible mechanics on damage champs or terrible CSing), or the group that think it has no relevance at all. One group berates people bc they don't understand the individuality of players and specific games (like you said it's important) and one group berates players bc they become frustrated focusing on what is "unfair" or outside their influence rather than focusing on their own game and knowing they will climb over time if they are better players.

If we are not talking about players who are boosted to a rank above their skill level (either through buying boost or baeing duo consistently w/ a higher skill friend who carries them) then I think I can create a solid argument that significant rank gaps indicate significant skill gaps in instances where there is an appropriate sample size (ie both players play ranked more than 20-50 games, or we are looking a average normals matching and both players play an equal amount of serious in their normals across all games). The argument is essentially the ability to climb or not. If you place a diamond smurf in bronze they will climb easily at least to plat level if they play their main role/champs, and if you play as serious as possible in normals to raise your normals mmr you quickly will reach an mmr where you are no longer matched w/ lower ranked players. I have a second account from leveling w/ a friend who joined (and I maintain it bc I like being able to play immediately if I have to dodge a lobby troll instead of waiting) and I was out of practice enough I placed both in bronze at the start of the season. I practiced, improved, and reached gold on the first account, then played the second one into gold. I had a significantly easier time and played a lot of stuff I wasn't used to/would do terrible in gold w/, and was still able to do okay in bronze. I switched to stuff I actually play and stomped up to mid silver (a couple of 14-1 streaks on my heimer when I stopped playing him support/adc) before I started slowing on my win rate. I have a 52% win rate overall on my main account and even w/ some games I played stuff I would only do average on and relied on my team to win the game while I went even and practiced, I still had a 60% win rate on the second into gold. I had riot delete some of the champs on the second account to organize the champs I owned differently (ocd runs in my family and I'm not affected to a clinical level but certainly like specific organization sometimes), and since I have been playing normals w/ mostly champs I main I have switched from being matched mostly w/ bronze and mid silver plus the occasional gold player, to being matched mostly w/ gold and plat players with the occasional high silver or low diamond player. Why did that happen? Skill difference. I'm a bronze level ADC at best and would probably get stomped by you as an ADC, but as jungle/mid/top I play high silver/low gold on champs I'm comfortable w/. When I was playing ADC or stuff like Rengar jungle in normals (stuff I would/have been crushed w/ if I try to play it in ranked) I certainly will get beat by silver and maybe even bronze players who are taking the game seriously. Does this mean they are gold level players? I'd argue no, but rather that I have no competency w/ those roles/champs. A diamond 1 trick rengar should have more knowledge about rengar and how to win w/ him than any bronze/silver/gold player you can find. They may not have knowledge about any thing else though that exceeds many of the bronze/silver/gold.

For this reason I believe that significant rank gaps (bronze/low silver vs gold, low gold vs plat, etc) do indicate a level of skill that the lower player is not able to reach currently. However, this is situation dependent as the higher rank player likely only excels at certain areas to their maximum level (their max rank + or - a division, maybe two). For some people their rank is achieved w/ mechanics, for some it is macro play, for some it's damage champs, while others succeed on tank champs. Additionally, the skill difference assumes that both players are playing at their best. If I have a shit day and want to blow off steam I play normals bc I am distracted, rather than ranked. I expect to lose to lower skill players on their main who are in a good state of mind if I'm doing that, which is why I'm playing normals instead of ranked. Some games people tilt and play much worse than they generally do, sometimes they are just in a state they shouldn't play bc they are too distracted, sometimes they are playing stuff they know they are bad at or just learning. I am not saying that higher rank means the player is always better or better at everything, but that they have some skill that exceeds the lower rank player and should not be upset or rude to a player who is lower skill bc they should expect that difference rather than being mad. At the same time, the individual nature of how each player achieves their rank, and the fact that no one plays 100% consistent means that lower rank players should often beat higher rank players who are on an off role/new champ/tilting hard and that won't change that there is something the lower ranked player could learn from the higher ranked player if they cannot get close to that rank. That's one reason I tend to use lolskill in normals to see how many people on each team are playing champs they are used to and/or their main role in ranked. That way I know if I'm in a game that's just let's have fun game or one that I should find challenging and be able to learn from.

Sorry for the wall of text but I wanted to give enough detail to try and support why I think it is possible to believe rank CAN indicate a significant skill gap w/out thinking that justifies being rude (and also argue that if you're aware of that gap you actually should be more polite and acknowledge it bc imo the lack of people doing that is part of where the issues w/our community come from). However, if I didn't convince you then that's fine too. We can both be polite to new players or people who are looking for help getting better even w/out agreeing w/ each other about how to do that/why it is important to do, and if enough people are actually kind and respectful to other players I actually do think league can be a comfortable and accepting environment. The majority of my games (at least 60-70%) are actually respectful and positive games, and that definitely wasn't true when I started playing a while back so I do believe a positive community in general is an achievable goal.