If your IP (and possible your browser) looks “suspicious” or has been used by other users before, you need to add additional information for registration on gitlab.com, which includes your mobile phone number and possibly credit card information. Since it is not possible to contribute or even report issues on open source projects without doing so, I do not think any open source project should use this service until they change that.
Screenshot: https://i.ibb.co/XsfcfHf/gitlab.png
Codeberg the community is very nice with strong focus on the right to privacy and free software, which I feel reflects itself especially in a lot of copylefted projects on the service.
Codeberg the collaboration platform is in my epxerience by the simple fact of critical mass quite a bit less ‘collaborative’ for many projects. There’s a couple projects with tight communities, and a lot of single dev projects with maybe a drive-by PR.
Codeberg the software runs on Gitea (/Forgejo) which is wonderful software - slim, simple enough to get everything done without being in the way.
There’s efforts to open up the gitea/forgejo forges to federation, which would be a very neat way to fix the collaboration issue and is - in my view - the way forward for open, decentralized collaborative software creation. It’s still quite a ways off (especially from bring mature enough to be used day-to-day) but when it gets there platforms like codeberg will be the first to adopt it and to also benefit massively from it.