I love the idea of having a non-congressmember as Speaker of the House to disrupt their uniparty swamp and it probably would be more helpful getting bills proposed and dealt with, but unfortunately Elon could not actually be appointed Speaker of the House.
Hate to throw Cold water on this, but as the Speaker is 3rd in line to the Presidency I'm pretty sure he needs to be born a citizen of the USA, just like the President and Vice President.