Any "given" name/ID (IE anything but the full hash) in a distributed VCS has to be mutable - without some single central arbiter of truth it's simply impossible.
I'm honestly a little surprised people seem to think they might be immutable - I guess maybe if people see "git" as "Actually Github"?
> Revocation in Sigstore. A recent post on this blog notes that signatures alone don’t tell you whether to trust an artifact; for that, you need a verification policy. This verification policy is a much more natural place to handle revocation than the identity layer; see Don’t Panic for an example. This allows us to avoid the scalability problems of global revocation lists (see CRLite for a discussion of these issues). The mantra here is revoke artifacts, not keys.