I wonder whether he's really thought about the technical ramifications, though. Even an edit button would have pretty major consequences and things could get into the weeds pretty fast if you had to start diffing edits to see who retweeted what at which point. This might be the kind of thing that would be a major distraction for Musk if he started to put his engineering mind to it, rather than just making a few snarky quips and letting people make of them what they will.