SpaceX's claimed superior capital payback economics are not sustainable at scale and rely on existing infrastructure rather than repeatable competitive advantages

"While Johnsen's claim that it's producing very fast paybacks on its current investments may be accurate, it's not clear that it will be able to scale up as efficiently. SpaceX had existing infrastructure that it used to provide more compute capacity to third-party customers like Anthropic and Alphabet's Google last quarter. That's not necessarily repeatable."