Sunk cost fallacy. Musk has wanted to create an “internet bank” named “X” since working on PayPal. His partners never let him name it “X” (probably because it’s an objectively bad name) so ever since then he has wanted to make “X” a reality.

I think he was planning on quickly rolling crypto out to every account to make some weird monetization scheme where he doesn’t actually have to pay anyone, but then by the time the purchase was finalized the crypto market went bust and a lot of people have lost interest.

I still think he has plans to do weird stuff with monetization (based off previous remarks he has made), but we will see if it ever ends up implemented.