As long as you're careful to always call it a "tax" (16th Amendment) and not a "taking" (5th Amendment), you should be fine.
I don't think that's quite how it works. I'd guess that a court would consider the substance of the law and not just whether it is phrased as a "tax". I think legislation like this would have a substantial risk of being declared unconsitutional on takings clause grounds.
I do not know if that would hold up if they're actually naming specific individuals (the shareholders) and demanding that they pay the tax in the form of shares (aka turning over property) rather than the dollar value of those shares. If they're not doing those things, I'm curious how they're targeting it.
And unless they're doing it in a way that doesn't grant the government voting rights, that's a guaranteed loss of control of those companies by current shareholders.
If you follow through some of the links you get to this paper which seems to suggest that the mechanism might be requiring issuance of new shares?
Issuance of new shares does not confiscate the shares previously held, but simply dilutes their value.
I'm not so convinced by their arguments. It has the vibe of trying hard to avoid seeming like a taking while accomplishing the same thing as a taking, which I would expect a court to pick up on and be skeptical of. Particularly with the existing composition of the Supreme Court I think its going to be hard to rely on such arguments.
What is the mechanism whereby this nationalisation of the AI industry will "guarantee that the trillions of dollars potentially generated by A.I. are used to improve the lives of all of us"?
Quoting from Senator Bernie Sanders Op-Ed in the New York Times today:
As you may know, Senator Bernie Sanders has recently started taking the idea of AGI/ASI much more seriously. Now he's proposing partial nationalization on the premise that AI is a uniquely valuable and important technology.[1] While this particular upcoming bill of his is rather unlikely to pass, I like that ideas are being proposed which are at least somewhat commensurate to the problem.
Quote from article: "Artificial intelligence will almost certainly be the most transformational technology in the history of the world."