Yasuo's Balance and the Feature of him being fed

Alright there are a couple of reasons I am writing this post. First of all, Playing with my friends is not a thing anymore the game has become full of trolls and people who take advantage of champion imbalances like Yasuo. My friends never want to play anymore cause when we are trying to level up my buddy who just started we have a yasuo on their team and he can completely carry in a 5v1 against Dr. Mundo, Lee Sin, Ashe, Blitzcrank, and Veigar. Its a 5v1 his ult did not even go off he did 1400 damage in 3 autos! 700 from 1Q! He was only 7/5! I was playing Mundo and I went 18/4 and still could not touch yasuo. A tank like Mundo did absolutely nothing to him. My friends have all abandoned the game now. Second, the matchmaking has become worse and worse as time goes on I am not trying to say it is the worst their are other games like "Overwat**" (not sure if copyright issues or anything.) have horendous matchmaking that either pairs you with feeders who have pretty bad match history or with people who are way beyond your skill level. I know its hard but come on we are tired of it. Third, Yasuo needs a nerf badly. Their are so many players out their that only play yasuo cause they find him either super easy, or super broken you guys tell me.

Want me to say more please ask.