The stock market is off to a mostly cautious start Tuesday after the best three-day run for the S&P 500 in 13 months, even as SpaceX keeps running higher since its blockbuster IPO.

But no trade lasts forever.

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And one hot AI trade that is starting to wind down is the "bottleneck trade," says Altreides Management managing partner Gavin Baker. The hedge-fund star is referring to companies involved in important facets of the artificial-intelligence build-out, like memory-chip producers DRAM.

"This bottleneck trade is nearing its end," he said.

He pointed to the decision by Japan's Ajinomoto, whose shares JP:2802 have soared this year, to refuse to lift prices on a product that helps insulate layers that connect processors to chips.

"Everybody's having Claude run 'What's the next bottleneck?' That was the game for the last year; the next game is what has enduring franchise value on the other side of these bottlenecks, whatever that is," he said in an interview with TBPN that aired Tuesday.

Baker then turned to SpaceX, where he was an early investor. He said the investing public will focus on a longer time horizon than quarterly earnings. "The first is just how quickly can they bring on terrestrial compute. It does seem likely that they monetize gigawatts at a higher rate than anyone else," he said.

"Everyone in the ecosystem is really incented to get land and power in the hands of people who can energize it, because everyone starts to make more money when the GPUs are energized," he said.

Earlier this month, SpaceX CEO Elon Musk, who's also the CEO of Tesla TSLA, laid out plans for solar-powered orbital AI data centers to address the growing artificial-intelligence energy demands. SpaceX has said its first AI satellite could handle 150 kilowatts of AI computing, with a goal of 1 gigawatt per year by late 2027.

"So how quickly they can add gigawatts matters," said Baker.

While he's pretty excited, alongside Musk, about the ideas of cities on the moon and asteroid mining, Baker said SpaceX has "much more tangible near-term drivers here," and figures the team at SpaceX may have more confidence in bringing those gigawatts online.