I think you missed the point: the domain has not been in Musk's control that whole time, as I had thought. His company X.com had it, then PayPal got it when it was created in the merger of X.com and Confinity, and PayPal kept it after Musk left, but then Musk got it back.
This doesn't contradict what you're saying, but note that the company was only re-branded to PayPal after Musk left it. I think it was just named Confinity after the merger.
> On July 5 2017, Musk repurchased the domain name X.com from PayPal
They even took a little jab at him when it happened
> "We are delighted to sell the domain x.com back to its previous owner"