Should `@` be really a valid git tag name?

Hello Git-Community,

by accident I did:

    git tag -a -s @
    git push --tags

in v2.25.1 and pushed the tag named `@` to Github and had some minutes
of fun to get rid of it again (see: https://stackoverflow.com/a/69211383)

A SO commenter pointed out, that git-check-ref-format forbids @ and
maybe I should report this as potential bug. Is it?


Best,
Benjamin

P.S.: I'm not subscribed, so please CC me.