I don't particularly have a problem with Codeberg or with GitHub, but if I were doing a software project and it were GPL-licensed and I didn't have an existing presence anywhere, I'd probably look at the FSF's Non-GNU Savannah. I have a pretty high level of trust that anything that the FSF does is going to be okay (and, frankly, it's one of the few organizations where there is necessarily a fair bit of trust in that the FSF can create updated versions of the GPL that GPL-licensed software can be used under anyway), and they've been running that forge for...checks...24 years now. I would bet that 24 years from now, it'll probably be more-or-less the same.

EDIT: I would add that it'd maybe be kind of interesting to have some kind of distributed forge. I mean, git is intrinsically distributed, but as I talked about in a recent discussion, issue-tracking isn't (though there is a distributed git-bug that I discovered in that discussion), and while you can do code review via email (and email is distributed), a lot of people use non-distributed Web frontends on forges for it.

Like, I think that it might be nice to just make forges distributed, make people not rely on centralized infrastructure in general.