The only silent-retag tooling available is by staff, not moderators. I've been reviewing the search and there are a number of questions that are already at the five tag limit. This is in part due to fedora, centos, and redhat being added to some questions. It isn't always clear which tag should be dropped to add the rocky one.
It depends on what the link is.
In the example you pointed out, it was easy to find the up-to-date link to the standard, so I edited the answer to use the correct link.
In general, there will sometimes be a new link with the same information, or - as the other answer points out - you might be able to find an archive link. You can edit (or suggest an edit), ...
For dead link it's a long process, but if you find one you can edit to add a web.archive's link.
Like in your answer I found that one; https://web.archive.org/web/20190115142142/https://http2.github.io/http2-spec/ that could replace it.
In the answer example it's good as the answerer put time to copy/paste the correct section, in case it's no longer ...