Both names are linkbait. I think 'Twitter' is less misleading than 'X', so it wins the guideline on points.
Not saying it's a strong case, just that it tilts that way. Others would call it differently and that's always the case with a close call.
Just because you buy something doesn't mean you get to change popular usage by decree. There's a whiff of corporatism about that which sticks in my craw.
(I am not, god help us, making any implicit point about the muskwars.)
