If you can tell it is AI generated, then it's going to be more trouble than it is worth.
Note "substantially" AI generated. If you've been paying attention to popular open source projects you've seen the sort of "contributions" and of course they should be dismissed.
If you have had generally good experience with GenAI, think not of your direct experience, but rather your experience with how others have used it, and that's more representative of the issues.
If you've seen a typical GenAI pull request, it's blatantly obvious. If it has been curated well, sure it's probably not feasible to know, but "slop" is easy to tell, and the target users have very slop contributions.