In other words, that regardless of whatever narrative the Youtube moderators or Youtube as a company wish to support while still claiming to have a neutral and fact-based attitude, selectively applying their own rules (and keeping the rules they do apply, vague) is the perfect tool.
Yep.
Now again, as to this particular question of links in comments on YT, I don't think they are doing anything selective here - at least I have no evidence of that. From all my experiments and these of a few other people, any link at all seems moderated immediately.
The fact that they allow posting links and showing them as clickable links in comments, while automatically removing comments with any, is not evidence that YT is doing anything selective.
It's just evidence that they failed to modify the code that generates the comments (which could have indeed just either make links non-clickable, or replace them with a mention such as "link removed, not allowed, see section xxx of the TOS"), leaving moderation entirely to an upper level of code which just removes comments altogether if they contain anything detected as violating some TOS rather than moderate comments and display them with moderation mentions.
The fact that they do not state this link-in-comments thing clearly anywhere (at least that I've read, if anyone finds that, please post) and lets people send comments with them while automatically removing the comment right afterwards may be, not particularly evidence that they are being selective, but possibly evidence that they do not want people to be aware of that restriction, so that they can gather thousands (possibly millions) of links posted by people all over the world and collecting that for various purposes.
In other words, by letting people posting links but removing the posts afterwards, rather than preventing them right off the bat (which would be very easy, just detect links when a user posts a comment, which is trivial to do, and display a message that links are not allowed, period.)
Finally and once again, if you still don't believe me about links, just try. Surely if they are indeed being selective rather than doing it for everyone, someone readind this is bound to manage to post links in a YT comment and have the comment stick for longer than a couple minutes.