The iPod was a peripheral to use alongside your MacBook, it was meant to drive Apple computer sales initially and it's not like it was Apple's first attempt at a portable device (Newton). Nokia was building telecom equipment (stemming from their telephone cable experience, the insulation being a product of their original rubber business) and military equipment along with a bunch of other consumer electronics before they got into mobile phones. Amazon released AWS because that was their infrastructure they had built for themselves to handle their massive e-commerce business.

Companies generally don't just jump into a totally new market unless they've already got some experience.

The SpaceX acquisitions of xAI and X have absolutely nothing to do with space. While I'm sure SpaceX software engineers benefit greatly from cheap access to Grok, it and X have no relevance to the core business of SpaceX. It's the same level as "huh?" if Boeing decided to buy up an AI company and social media platform. The only reason xAI and X are even part of SpaceX is because Musk fucked himself with being forced to buy Twitter and he decided to bundle them with an actually profitable company.

Spacex has no existing customer to satisfy their future launch ambitions with Starship, hence data centers in space, just like they did with starlink to provide the necessary demand for Falcon 9. The launch business is not profitable without a regular cadence, too many fixed costs - ground infrastructure and personnel.

X can supply training data to to Xai and Grok is heavily integrated into X so there is some synergy there.