Looks like owner of Ryujinx changed and now is developed by someone else? The top contributor for this is gdkchan, the previous owner and main developer. So this is not simply a fork, but changing ownership of the original repository. Is that right? It makes sense, because what happened previously is that gdkchan got a message (or visit) from Nintendo to stop working on the emulator. That’s all. There was no cease and desist to the entire project, or anything like that (unlike with Yuzu).
Edit: Another hint that this is the original repository is, that a message is displayed that I have blocked a certain user who contributed to this repository. This message does not popup on any of the forks.
Edit 2.0: I may have been wrong: https://docs.github.com/en/repositories/creating-and-managing-repositories/transferring-a-repository
If the transferred repository has any forks, then those forks will remain associated with the repository after the transfer is complete.
And looking in the list of forks, the oldest one seem to be 1 month old or so.