Facebook (the thing I think people will agree destroyed MySpace) was not started by someone fed up with MySpace saying “I’m going to make the same thing, but I’ll moderate it differently!” It was started before MySpace had reached peak popularity, by an entrepreneur with a totally different product vision and way of looking at the world. Elon’s hypothetical Twitter-clone would probably be more like Gab, Parler or the Trump thing: Twitter, but with less moderation and some sort of weird gimmick, like “starting midnight Tuesday, I’m giving a free Model 3 to the first 1000 people who sign up!” or “I’m hosting a quarter of the load on servers on StarLink satellites!”

Twitter won’t be destroyed by someone making a slightly different Twitter clone, it’ll be destroyed by something that re-imagines entirely in a way that also supplants it, and it’ll probably come from someone we don’t know yet.