“Deliberately” making bad plays? If it’s a “bad play”, it’s not deliberate. If it’s deliberate, it’s trolling. There is no in between. There is no need for a special “low key toxicity” term to describe this.
Jungle is not obligated to gank any particular lane or any lanes at all, in fact. There are cases where it is more beneficial for the jungle to focus on farming, counterjungling, getting vision of the enemy jungle, etc - instead of ganking. As an example of one of these cases, if all lanes continue pushing past mid lane, there is hardly a good opportunity to gank that outweighs the benefit of counterjungle. Keep in mind that your jungle’s job is not to win your lane - it’s to win their lane - the jungle. If they are able to outscale the enemy jungle, and especially if they are able to force the enemy jungle to lose objectives/gold by counterjungling/warding, that is their right to make that decision. They do not have to gank you.
“Whenever you meet in the map” - what do you mean by this? Are you saying that someone does not “go in” to a fight that you go into? Nobody has to listen to you or do what you want them to - you aren’t the boss. If they don’t want to fight, that’s their right. I have virtually never seen someone do this without being provoked by someone flaming them or trying to boss them around.
“A player refusing to play with the team, going alone farming a lane, and just refusing to participate in team fights all while staying AFK in base for small periods of time” - there’s so many things here. Farming is not against the rules. Splitting is not against the rules. You do not get to dictate how other players play, and you do not get to blame other players for your deaths/lost objectives simply because they didn’t listen to you. It is completely possible to freeze 4v5 in a lane - or 2v3/2v2 in two lanes - while the other teammate split pushes. Going AFK for “small periods of time” - first of all, they may be waiting for gold. They may be attempting to think about where they need to go. Unless “small periods of time” becomes “large periods of time”, this isn’t anything punishable.
“Build items that in no way will work or help the team” - You don’t get to dictate how someone builds. Their build is primarily to ensure they can do the damage, have the abilities/attacks they need, have the utilities they need, etc - not to help you be a carry. Unless someone is flat out building AP on a champion without any benefit from it (i.e. absolutely NO AP scaling, absolutely NO benefit from CDR, absolutely NO benefit from secondary effects of AP items, etc), then you don’t get to say that it “in no way will work”. As one example, there are many AP items that go well on the dozen or so champions with no AP scaling - Gunblade, Nashor’s, and Lich Bane to name a few.
“Just troll builds” - Please feel free to show a screenshot of a game in your match history (with the name blocked out) where someone actually did a “just troll build”. I suspect you’ll be hard pressed to find one.
“All while playing bad on purpose” - this is another oxymoron - someone cannot “play bad on purpose”. They’re either playing bad because they are bad - in which case it’s not on purpose - or they’re trolling and intentionally feeding/griefing. There is no in between.
“Going 1v5 against the enemy and dying” - Again, either this is intentionally running it down/griefing; the player is bad; or they are getting caught out or picked off. There is no in between.
To summarize - your thread is an example of what is wrong with the community. You are attempting to do anything possible to find fault with others that is causing you to lose games and/or be frustrated. You have gone so far as to attempt to blur the lines between intentional griefing/trolling/feeding behaviors and legitimate gameplay where the line is crystal clear. Defining this vague “low key toxicity” term as simply “players who are bad” does not do any good - you can call it what you want, but players will never be punished simply because they are bad at the game, period, full stop, end of discussion. Nor will you ever be given some magical authority over other players’ builds, play styles, decisions, rank, etc - especially when you make a post such as this where you show literally no understanding of how teamwork actually works.
Put quite frankly, not only is your post useless as you simply redefine “being bad” as “low key toxicity” to attempt to justify them getting punished for just being bad, but you flat out lie in your post by trying to claim you’re seeing this behavior super frequently. You’re going to have “bad” players - one team has to win, of course - in every game. Deal with it. If you want to be matched with players of higher skill, you need to improve your skill. Riot will not punish innocent players for “low key toxicity” (being bad) simply so you can climb when you don’t deserve it.