(Long rant) Why is Platinum so toxic?

Alright so let me get this straight, I will and have never claimed I'm a positive player. I like to bm with mastery emote and sometimes ? in all chat. But I usually don't flame my teammates. But ever since I climbed from silver to platinum this season the toxicity is so insane you won't believe it. Almost 90% of the games I have the flaming starts even in champion select. Example: I'm firstpick and I tell my team not to ban yasuo but they still ban it for no reason (I have a good winrate on him and he's my best champion). Okay, that's fine, they have the right to do that I guess and I'm not gonna bother try reporting them for that since everyone hates yasuo and im sure you cant get banned for doing that. But they have the nerve to say they banned it because "I dont want you to feed" And then in game they have the most deaths on the team even though their jungler's been camping my lane the whole time? Really? And if by some miracle neither team bans yasuo and I get him it gets even worse. I try to freeze early unless i know i can get an early firstblood kill or my jungler is around. But there's bullshit like counter matchups or I get camped under tower. And it sucks because I know my jungler will never help me just because they cant get over the fact that I main yasuo. If I feed my team will probably spend the whole game flaming my ass, and if I win lane but my team loses they'll blame me anyways. I never had these kinds of games in bronze, silver or gold. So why the fuck is Platinum so toxic? I understand that everyone wants to get to diamond but isn't that the same case with silvers wanting to get to gold? I need some fellow plats or former plats to maybe help me out here because I just can't understand the depth of anger that platinum players have. And sometimes it spreads to me, too.

tl;dr why is plat much more toxic if it has similar environment to lower elos