> if there was any evidence that he actually compromised US national security he would already be gone.

It's likely the story coming out like this is the best mitigation they can come up with, if AI is a national security interest of the US and he's granting a Chinese asset access to said interests. He's already conspiring with a foreign government against the interests of the US.

That he's extremely visible in his role is probably the only reason he's still around, until next week or whenever. The US doesn't vanish prominent CEOs like that, that's more a China thing.