Why does a champion like teemo even exist in this game?

RIOT said that they want every champion to be fun to play and to play against! And Teemo is really NOT fun to play against! Laning against a Teemo as a Champion that relies on Autoattacks is hell. Nothing else. You are literally out of the game just by Teemo existing in your lane.

Playing against teemo makes you want to quit the game, nothing else. hes not fun to lane against, having his mushrooms everywhere is not fun, being slowed all the time and afraid tzo take one step when low is not fun, NOTHING in playing against Teemo is fun!

That Champion is the definition of Anti fun! If there ever was a picture that would fit the term, it would be Teemo. And lets be honest, most Teemo players are toxic as hell as well, spamming laugh, and now spamming emotes. But why not, the champion basically promotes toxic behavior.

Just rework this Champion already, its not even like hes in a good spot anyway. Best thing you can hope for is that you trake the Toplane out of the game and then your team has to win from there. Just rework him, I dont care how! I dont care what hes doing after! Just take this toxic anti fun champion out of the game!

EDIT: The first three comments in this thread already say it all. Noone can even give a reason for this champions existance, they just want to troll around. So again my question, noone can give a solid reason for this champion, other than to try to provoke people, why does he exist! The whole champion design goes against RIOTS policy! They removed way less toxic things for being "anti-fun"