> They know how to ignore a PR if they don't want to review it

How well does that scale as the number of such contributions increases and the triage process itself becomes a sizable effort?

LLMs can inadvertently create a sort of DDoS even with the best intentions, and mitigating it costs something.

Wait and see, then change the policy based on what actually happens.

I sort of doubt that all of a sudden there's going to be tons of people wanting to make complex AI contributions to LLVM, but if there are just ban them at that point.