You can no longer upload a PGP signature to PyPI, if that's what you mean. That was phased out last year (to virtually no complaint since nobody was actually verifying any of the signatures, much less attempting to confirm that their keys were discoverable[1]).
> to virtually no complaint since nobody was actually verifying any of the signatures
And this is in no way a consequence of pypi stopping to host public keys right? Say the whole story at least… Say that there used to be a way to verify the signatures but you dropped it years ago and since then the signatures have been useless.
If it did, it was well before I ever began to work on PyPI. By the time I came around, PGP signature support was vestigial twice over and the public key discovery network on the Internet was rapidly imploding.
(But also: having PyPI be the keyserver defeats the point, since PyPI could then trivially replace my package's key. If that's the "whole story," it's not a very good one.)
This attestation doesn’t change a ton with that, though. The point is to provide chain of custody — it got to my computer, from pypi, from ???. The PGP signature, much like a self-signed android app, verifies that it continues to be the same person.
The critical difference with this architecture is that it doesn’t require key discovery or identity mapping: those are properties of the key infrastructure, similarly to the Web PKI.
Your self-signed app analogy is apt: self-signing without a strong claimant identity proof is a solution, but a much weaker one than we wanted.
