> There are a few of these "maintainer said no AI pulls, so we forked it" in the wild already and I am really interested to see how it all pans out.

There are also forks that go in the other direction, i.e. forking to avoid AI contributions upstream: https://drewdevault.com/blog/Forking-vim/

And promises to do so if it becomes necessary: https://human-emacs.org/

Will indeed be interesting to see how it all pans out.