> one country every 10-20 years gaining nuclear weapons and basically no tests happening

This past week had a test in both N. Korea and Iran, so I don't think that is accurate.

> I'd say that's a massive improvement.

Oh, yes sure it's an improvement. But if we only have two countries intent on starting a nuclear war, thats already enough to hose the whole planet. And I am far from confident that we can safely say we aren't there.