I believe the feature is that you have a pending unreleased video and go to an llm for tips. When getting the tips it uses the pending video content and your recent videos info as context. So there's no holding back unlisted info short of not letting the user use it for their upcoming videos at all

And then the attack is to trick this recommendation system into putting a link out

I actually the attack is very likely already soft defeated by an interstitial telling you that you are leaving the site though, it would be weird if they didn't do that in general from this surface