I think he wants to turn X into a western WeChat that will include payment features. It is only logical for him to include crypto in that due to the large crypto community that is highly active on twitter. Notice I use the term crypto and not bitcoin, well that is intentional because ultimately twitter probably creates their own stablecoin to use on the platform. Maybe bitcoin is one of the "cryptos" that is part of some X feature set but let's not hold out any hope that Elon will turn into Saylor 2.0.
I think we will get a Saylor 2.0 at some point (and maybe even bigger if they control a large tech company instead of a small one) but I doubt it will be Elon. Happy to be wrong.