I am ashamed of GitLab.

Don’t be. Gitlab has to comply with the law.

It’s the law that’s broken, not Gitlab.

It’s absolutely ridiculous they took it down even though Nintendo didn’t DMCA the Suyu project directly.

Um, no. If shitty corpo X (ab)uses the DMCA to send you a takedown notice for some project and you also host a fork of the same project, you must take down the fork too.

“You see, while this might be the exact same code, the name is totally different, so we don’t have to take it down!” will not hold up in court.

Whether the DMCA request is valid or not is an entirely separate question. You must still comply or open yourself up to legal liabilities.

The process to object to the validity of the request is included in the screenshot.