There is some risk that over time people will be able to do more with less, and eventually you can train an AGI with a few dozen A100s. If that happens I agree there's nothing you can do, but until then there is a chance.
At the end of the day all these are just calculations, of which you need thousands of processors to do with high accuracy. Pretty much what you're suggesting is a global police force to ensure we're performing the 'correct calculations'. Having to form an authoritarian world computer police isn't much of a solution to the problem either. This just happens to work well in the nuclear world because it's hard to shield and the average person doesn't have a need for uranium.
It would be better if we didn't need to do this, but I don't see a less intrusive way.
Of course, if you don't think there is a real existential threat then it's pointless and bad to do this, it all depends on that premise.
The question is, is an authoritarian nightmare that much better than getting tossed into the meat grinder?
If the choice was between those two extremes, I'd take the authoritarian nightmare.
Extinction is forever, dictatorships end.
And no country will ever make the same mistake again. Because the west promised to protect them from aggression. But when the time came to do just that - everyone involved dusted off their copy of Budapest memorandum and handed it over to the lawyers.
Sorry for digression. Carry on.
It was not very fair from civil war already, with the aborted coup. Could you imagine if the Wagner group became a nuclear power??
First nuclear weapons were used in 1945, almost 80 years ago. Today, out of ~ 200 countries in the world only 9 have nukes. Of those, only 4 did it after Non-proliferation of Nuclear Weapons Treaty. South Africa had them and gave them up under international pressure. Ukraine and other former soviet republics voluntarily gave them up after the breakup of the USSR.
So, yes. Unfortunately we still have nukes and there are way too many of them, but it's not like non-proliferation efforts achieved nothing. Iran, a large country with a lot of resources, has been trying to get them a for a while with no luck for instance.
And for frontier AI research you don't just need matrix multiplication, you need a lot of it. There's less than a handful of semiconductors fabs globally that can make the necessary hardware. And if you can't get to TSMC for some reason, you can get to ASML, NVDIA, etc.