> Codeberg might ironically become a boon to AI companies with this policy, as well, by effectively doing a bunch of curation work for them, if not by providing outright untainted training data.

Or the opposite, as the rules are you cannot use AI, all the attribution will be removed, but sure enough there still will be a bunch of AI written code there, people will just have an incentive to mask it instead. So it ends up being a place where AI/human code will be even harder to see the difference between, compared to GitHub, where people apparently have no shame in just attaching claude's username to their commits.

Why would you mask AI code and place it on Codeberg instead of some other place where it won't be deleted on sight? The only reason you would do that is to attack Codeberg.