Kaceytron is a bad example to use, because her stream does the opposite of what Tyler1 did.
Kaceytron's viewers are there for boobs and to rage at her. She is the epitome of everything they hate in the game, and she makes people who troll/feed/afk look even dumber than they normally are. As such, no one wants to emulate her actions. If Kaceytron were to be lifetime (not perma-) banned however, it'd create surge of streamers trying to emulate her success, making the situation worse than it was before.
My understanding is that Meteos hasn't behaved in a way that has resulted in him being permabanned, which would imply he's not toxic in game regularly enough to be punished. Remember, Riot doesn't ban people for what they out loud at their computer. I am curious why so many Tyler1 fans cry out "but Meteos!" though, does did Tyler1 regularly complain about him on stream?