Again, to be clear: the standard does not stipulate GitHub or any other specific identity providers. The plan is to enable GitLab and the other Trusted Publisher providers in short order.
This is exactly the same as Trusted Publishing, where people accused the feature of being a MSFT trojan horse because GitHub was enabled first. I think it would behoove everybody to assume the best intentions here and remember that the goal is to secure the most people by default.
It's said explicitly in the second sentence in the usage docs[1].
> Attestations are currently only supported when uploading with Trusted Publishing, and currently only with GitHub-based Trusted Publishers. Support for other Trusted Publishers is planned. See #17001 for additional information.
This is exactly the same as Trusted Publishing, where people accused the feature of being a MSFT trojan horse because GitHub was enabled first. I think it would behoove everybody to assume the best intentions here and remember that the goal is to secure the most people by default.