Yes, it's an over-simplification. But this is an area of the country where capacity factors are in the 25-30% range:
https://www.eia.gov/todayinenergy/detail.php?id=39832 (the Ute Mountain Reservation is in the very Southwestern corner of Colorado, a little bit of New Mexico, and a little bit of Utah:
https://www.google.com/maps/place/Ute+Mountain+Reservation,+...)
So even if you discount the capacity by a 25% capacity factor, and use the lower cost per reactor that I originally quoted, this is still cheaper than nuclear. And that's just the up-front investment. Operating costs are much cheaper for solar as well, the majority of the cost is in the initial build.
Given that transmission isn't free, there are areas of the country where solar has a lower capacity factor than this, and solar and wind take more land, there are still cases where nuclear may be a better investment. I'm just pointing out that there are plenty of simple, economic reasons why solar and wind are growing at a much faster rate than nuclear; it's cheaper overall, it requires less up-front capital, etc. Nuclear is likely to fill niches for a long time, but investment in nuclear is not going to be the major way to decarbonize.