While he may drive a Tesla and use Starlink, he didn't create SpaceX or swoop in and take control of Tesla as an obsessive customer with an agenda as a customer.
I don’t think that that entirely explains why Musk Twitter isn’t like Tesla or SpaceX, but I can’t imagine its not a significant factor.
(I also think that, distinct from his customer-agenda, him seeing it as an opportunity to relitigate his finance app history getting booted as CEO of X.com twice before it became PayPal is an issue that impacts more than the names he has used for the companies used in the Twitter acquisition.)
But this is not the difficult bit in building a competitor. The difficult bit is to make people switch en masse.
He opened up the arena.
Zuck and the threads team are probably thinking about that