Would the RNG complaints lessen with ranked?

If the same people maintain high ELO in normal league, will the "RNG team" debates die down or lose traction? I guess not Still, you know there is a problem when people end with 5 3-star champions and something like 10 full items

No, there will always be a subset of players that don't understand the amount of skill behind manipulating the RNG.

So let's start by saying people that complain about the RNG are not completely wrong. It exist and getting 3 FoN and four 3* WILL happen and will lose you and win you a game or 10 at no fault of your own or the enemies.

Should items remain how they are, you will lose games exclusively to no mistake you made since the opponent can just get more.

The thing is the frequency in which you get these sprees, for some it's entirely possible (due to it being random) that every game they only get negatron cloaks every single item for 100 games. This is possible (highly unlikely though), the point is that the ladder will never be sole based on skill of the players even in the upper echelon. League is still mostly a skill game, yes luck sometimes works in your favor with allies, but if you can constantly go 20/0 on a champion, you will probably be challenger in less than a month.

TFT is not like that. Currently there are 3 ways to play. RR like crazy, Eco up no spending, and Eco + rolls at ~5 for 2 stars.

Comps that are good already exist. Assassin/ninja, Wild/Shapeshift/Dragons, Glacial/ranger, Imperial elementalist. With a few small deviations of the same builds. Now that players know this, to climb getting Blade-masters or Brawlers is just bad. So what does that mean for ranked? If you get your hands on one of these comps you probably win. If you get presented with brawler blademaster 90% of your rolls, you lose. You might know better, but if all you get is Fiora early with tristana, then some aatrox with GP what choice do you have?

Do I think players will be able to maintain the highest rank challenger consistently? Yes, do I think many players will be there that shouldn't be yes, but also I think players that are lower Diamond could possibly be better and just be unlucky and the higher elo players just know how to abuse them being unlucky.

Removing item RNG on quantity in my opinion is a must. Slighting the cards towards what you are building a bit is also likely needed, imagine going full nobles, because you were perfectly manipulating the RNG and then at level 8 when your comp is complete and are at 100HP playing perfect, you lose because the only 5* you got was MF, Yasuo and Swain. With a "tilted" system, Kayle would more likely appear since the game understands you have nobles and MF/Yasuo and Swain would do nothing for you.

TLDR: Games will be won by RNG, not as many as people are complaining about, but enough to screw up the ladder that Riot should do a bit of something about it.

The most important thing is fix all these bugs, I can't believe that this game is going to be ranked soon and it's still in this state even on the PBE it's riffled with bugs and champions not attacking. This game is not "structurally" ready for ranked.