Hagrid does not distribute user ID revocations
https://keys.openpgp.org/about/faq#revoked-uids says:
When an OpenPGP key marks one of its identities as revoked, this identity should no longer be considered valid for the key. And this information should ideally be distributed to all OpenPGP clients that already know about the newly revoked identity.
Unfortunately, there is currently no good way to distribute revocations, that doesn't also reveal the revoked identity itself. We don't want to distribute revoked identities, so we can't distribute the identity at all.
There are proposed solutions to this issue, that allow the distribution of revocations without also revealing the identity itself. But so far there is no final specification, or support in any OpenPGP software. We hope that a solution will be established in the near future, and will add support on keys.openpgp.org as soon as we can.
This is a clear statement of the problem, so i'm opening this issue to track possible means of resolution.
@valodim, i think you wrote that text originally. do you want to point to the "proposed solutions" here so we can evaluate which ones seem plausible?