It is a security issue if the presence of a commit or tree in a repo is supposed to be enough to get GitHub to nuke the repo, as this then allows malicious user

It is a security issue if the presence of a commit or tree in a repo is supposed to be enough to get GitHub to nuke the repo, as this then allows malicious users to convince GitHub to nuke any repo they like, but GitHub can instead deal with this more sensibly and not make it a security issue.