delete-tag the pushes the against the hard-coded remote 'origin' .
This failed for me b/c i renamed this usually to 'o' for laziness' sake ;)
delete branch figures the remote out from the branche's remote which doens't work for tags.
However, the current branch's remote could be used as a fall back which to me would make sense in most cases.
Another idea were to make the remote a CLI option or could be even put into the git config.
Note sure if this issue comes up in other extra commands as well in which case a consistent behavior across all commands would be appreciated