Its a choice they're totally allowed to make, I just wish we'd get an updated mission statement[1]:

"The mission of Codeberg e.V. is to build and maintain a free collaboration platform for creating, archiving, and preserving code and to document its development process."

Amended to include at the end ", as long as you use the tools we find agreeable."

[1]: https://docs.codeberg.org/getting-started/what-is-codeberg/