Support for Codeberg is being discussed here[1]. I think there's broad consensus among PyPI's maintainers and admins that more publisher providers are desired, but we also need them to demonstrate strong key management and rotation controls due to the degree of trust and access that becoming a publisher provider grants them (effectively, they become the PyPI credential broker for the projects that use their service).
(If you pan through that thread, you'll note that one of open issues with Codeberg is that their underlying server wants to store OIDC private keys on disk at the moment. This is okay for small deployments of personal services, but not for something that PyPI needs to federate with and trust.)
Of course: In principle we'd welcome a change, but there are technical difficulties in perpetuity.
So I, as someone who does my builds locally, can never have attested builds?
Will PyPI be presenting warnings or statements of caution which might cause users to be concerned about using my distributions? Or imply that my build practices are somehow inferior to depending on a third-party build system?