Currently, all hyperscalers are in an arms race to buy energy, data centers and GPU capacity for the big struggle of "who will win the AI war?" - the Amazons, Googles, Oracles, Metas and Microsofts of this world all want to be the one winner that takes it all.
In this case "it" or rather "they" are the consumer AI market (a la ChatGPT) and the B2B/corporate AI market (for enterprises and their vertical AI applications) - and yet to be built!
The race is run before we get to know who the killer apps are, and whether there will be one (if not: another bubble to burst, much worse this time than in 2001).
Perhaps the XAI/SpaceX integration could be done for the same reason that Amazon fired 30k white collar workers: enormous amounts of cash is needed for the investments in AI infrastructure.
Now XAI alone may struggle to raise that much; with SpaceX integrated, there are government funds to tap into as well, and it's less clear to separate the space travel business from the AI business, which might be intentional. Amazon shedding 30k people means approx. $6 bn in annual savings, capex that can be redeployed (cf. https://www.youtube.com/watch?v=7sk3qmIQZnI)!
EDIT: Typo fixed
