In your use case, only the poster could do it. Nobody could rug-pull Darth except Darth.

But could a bad actor do a misleading switcheroo on his own content? I suppose so, in theory. In practice, would anyone bother? Maybe. What could happen in response? Well, there would be the edit history demonstrating his bad actor-ness.

But yes, I think you could come up with a situation where something you didn't like would happen.