According to this, example.com is now the "preferred" example domain and should be used over other domains. Those other domains are blacklisted and aren't allowed in new posts.
Currently, though, there's a user that's going through the posts with "site.com", etc. in them and changing it to example.com. This is often the only change.
I've been rejecting them as too minor, but they often get approved, causing me to second guess myself. Take for example this one.
Should these edits be approved or rejected?
xxx.com
unchanged!xxx.com
, that was just an example. And they aren't links, per se, but examples in code blocks. But yeah, a real link to such a site should be edited out.