Meta isn't Google. They don't seem to give up on products easily. I would guess they are willing to lose money for quite a while.
I think of how persistence in the browser wars paid off first for MS, then for G. If MS had built an absolutely kickass, standards-compatible browser, I don't think Chrome would dominate today. I just wonder whether Elon's dysfunctional X is creating a similar opening.
In the end, I think it will all come down to Elon's grappling skills, since Zuck has reach and quickness on him in the striking combat. If Elon can get inside and take Zuck to the floor and use his weight to his advantage, I think he can save X.