I think the reason why lee sin and yasuo winrates are so low is because of the amount of people playing them a bit and doing poorly, and their massive pickrates are because the champs are fun to play. Because lee sin and yasuo aren’t bad champs, their winrates are just dragged down because of the number of non mains just playing them a bit.
I think this is kind of true. And I think it was more true historically.
But then we look into how many games on Yasuo and Lee Sin people have... and even the "casual-just-playing-lee-sin-for-fun" people often have a TON of games and high mastery on them. This gets into our Breadth vs Depth Report that Riot Novaasterix (forgot his reddit name RIP) did that looks at not only how many people play a champion, but how much they play that champ