The link says that it supports only Fedora 38. Also, the main page for COPR says (in a small font): "NOTE: Copr is not yet officially supported by Fedora Infrastructure.". As I understand, it is the repository for packages uploaded by random anonymous users (not related to the authors of yabridge or Fedora).
That is correct. I didn't think specifically about Fedora 37; it's been a while since I upgraded to 38. I couldn't find F37 builds, even though that's around the time I tested yabridge. You might consider switching to 38 anyway, as 37 is less than two months away from it reaching EOL -- F39 release date (17 October) + 30 days.
> As I understand, it is the repository for packages uploaded by random anonymous users (not related to the authors of yabridge or Fedora).
That is mostly correct. It was not uploaded, but built on the Fedora infrastructure, following the RPM spec you can reach from the builds tab [1], for example the latest change located here [2].
There is an amount of trust you have to give to the copr author, but you can also check the rpm spec file [3]. Important quick checks are around the source0 lines.
> Also, the main page for COPR says (in a small font): "NOTE: Copr is not yet officially supported by Fedora Infrastructure."
Getting a package shipped into the Fedora base repositories seems rather bureaucratic and I understand any hacker that doesn't want to use their own time to deal with that.