> Politically-motivated forks by non-developers have happened in the fast

Sure, but is that really what Codeberg/Forgejo is? As far as I can tell, the contributors have demonstrated they have technical capability (look at Woodpecker or Codeberg.org itself for examples), so they're not non-developers.

And the fork happened as a way for them to protect codeberg.org, as the main software they were using for codeberg.org seemed to have volatile ownership, so it's a move to avoid any potential issues, not just a "politically-motivated fork", but a "organization survival fork".

As a counter-example, look at iojs, which was also a fork of nodejs, because of disagreement of governance. Eventually, nodejs conceded and eventually the two projects were re-merged with each other, with changes from iojs being accepted into nodejs.