That's true, but also requires that companies believe those subsidies will remain in place over ~20-30 years. Assuming US elections remain fair, that's not going to be the case. By contrast solar / wind subsidies are effective since the bulk of their cost is up-front, so you can generally rely on getting full value out of those subsidies.

Subsidies can certainly delay things at this point, but it's hard to see how it'd stop it.

I agree. Subsidies will delay, but they will not change the outcome.

Considering we are racing against CO2 release and the warming planet, I worry that the delay makes a large difference in outcome, not for energy breakdown, but in quality of life for humanity.