Yes, Yasuo is bad. Yes, it's because of Conqueror, some bugs, nerfs to his base stats, and itemization problems. Yes, his winrate is terrible. No, people won't ban him any less. :
Ahri Matchups Results From Champion.gg Left Me Speechless : r/AhriMains
Urgot and Yasuo likely slide in competitive after patch 9.4 - WIN.gg
Yasuo - ChampionMastery.GG
Pyke surpasses Yasuo as the most-banned champion in ranked League of Legends - Dot Esports
LoL Builds - Champion GG for League of Legends by lriccardo - (Android Apps) — AppAgg