Do we even want a bunch of people contributing slop upstream when (assuming it does anything worthwhile in the first place) somebody has to actually review/correct/document that code?

A handful of well intentioned slop piles might be manageable, but AI enables spewing garbage at an unprecedented scale. When there's a limited amount of resources to expend on discussing, reviewing, fixing, and then finally accepting contributions a ton of AI generated contributions from random people could bring development to a halt.