When discussing "fixes" to champion select, no one seems to remember this tiny little fact.

Riot does not consider not playing the meta to be the same as being toxic.

There is nothing in the Summoner's Code that says that there can't be two midlaners or that you have to have an ADC.

Even if you could "fix" all the toxic players, they would just stop technically typing harassment in chat before trolling, and thus, no longer be considered "toxic." Riot only cares about their chat; it does not consider the actual gameplay portion of their actions to be an offense.