Whats the point of playing anything other than zed and yasuo

I really don't get it, whats's point of playing lux, syndra, mages, or anything other than zed, talon, and yasuo in mid lane, those 3 out damage every champ in the game, they are played in top, mid and bot, Domination runes tree so strong, zed can easily shred 75% of your hp with his basic combo at lvl 3, and ignite to finish, talon can finish you at lvl 2, it's already known, yasuo with his toxic kit, and the true damage of conqueror, and all riot does is to keep buffing them every patch, lethality items are disgustingly strong, especially duskblade, even in bot, the top win rate adc is mf, at 53%, just because she doesn't heavily rely on crit as lethality items are way better for her. I really don't get it, what's the point of playing anything other than those 3 champs in mid???