Board Thread:General Discussion/@comment-37194541-20190820103629/@comment-24692230-20190820104842

Policy aside, Fandom has an extension that makes it so that some global groups (like staff and vstf) can't be blocked, which shows up as the unblockable right as mentioned above.

Also, you're allowed to block anyone for any reason as long as it doesn't violate ToU (or the wiki's local policy if they have one). If a block goes against the ToU then you can report it to staff via Special:Contact and they're deal with it.