There is a problem with this, though; it is quite often that when somebody doesn't get what they want, or somebody else picks something strange, they start being toxic either in chat or by the way they play (or don't play if they AFK). The group not kicking somebody they don't want to team with (say, someone using a new champ in ranked) is just another excuse those people will use to be toxic, sometimes perpetuating a cycle of toxicity.
Kicking a player who may be toxic sounds good in theory, but actually putting immediate disciplinary methods in the hands of the average player is a sure way to punish thousands who didn't deserve it.