The US would not be net negative growth without government spending. Other components of GDP grow a lot, outside of recessions.
Sure if you immediately stopped government spending today we'd have negative growth today but that's not because other things aren't growing, it's because you just removed part of the base that existed last year. That would be true of literally pretty much any economy ever, or anything that's growing and you decided to remove a chunk of the base from.
And yes I absolutely believe the government does not have better generative AI than Anthropic or its competitors.
Covid shutdown should have killed our economy, nothing short of government spending prevented otherwise.
So many people in the US live a paycheck to paycheck lifestyle, that the covid lockdowns without government spending would have likely devolved into zombie apocalypse territory where hungry people were ransacking homes in more affluent neighborhoods (yes, even occupied homes). This is why people also bought lots of guns and ammo during Covid. You may think those people are crackpots, but I feel we actually got very close to it happening.
My local food bank (big city) ran out of supplies just as they announced the first waves of stimulus or whatever they called it (the weekly checks). So I’m pretty sure we were literally only days away from that being a reality.