CLAs can be abusive, but not necessarily. Apache Foundation contributors need to sign CLAs, which essentially codify in contract form the terms of the Apache 2.0 license. It’s a precaution, in case some jurisdiction doesn’t uphold the passive licensing scheme used otherwise. There’s also a relicensing clause, but that’s restricted to keeping in spirit, they can’t close the source.
Codeberg is run off of donations, they have no service contract revenue. Nobody, much less a volunteer, wants to commit to a 5 or 10 year service plan like that, it’s not sustainable for a small project from a non profit.