Musk likely has his own motivations. Who calls a Constitutional Convention? Would would you need both parties to agree? Does it take a majority of the states to make it happen? There is an amendment process, but a new Convention would go beyond that. Seems difficult to get the red and blue parts of the US to agree on anything that substatial.
I would do that if the delegates were actually interested in ratifying something that serves everyone rather than entrenching the power in the hands of a few people. I don't trust the Republican Party as it is organized today to do that, based on the actions of their president and their senate and house.
