This is not my experience. As a PhD student I've already had a (strong) disagreement with my thesis advisor about whether to submit a paper or not. My advisor thought I shouldn't, I thought I should. In the end, I submitted it and it got rejected and that's where the whole affair stopped.

Actually, I really can't think of how my advisor would tell me not to publish a paper, except to suggest that it's not ready for publication.

But perhaps, as is often the case in these conversations, we're talking about different "academia"'s? I think there are differences between fields and between different countries' institutions in the same field etc.