Knowing nothing about the intricacies of building nuclear power plants, but agreeing whole heartedly with you that humanity dropped the ball when it came to advancing the tech and construction of large scale plants, I am hoping this will have a positive effect.
Large scale plant construction is hard, takes a long time and the knowhow is disappearing (see recent issues in France with their latest project).
With a miniaturized plant the time to market is quicker, which hopefully will start having a positive effect on peoples opinions sooner when it comes to nuclear power.
It may not be optimal, but it has the potential of changing things for the better.
I in general am in favor of scale to make the grid CO2 free. However, doing it with PWRs is just very sub-optimal. A 1.5GW plant is basically a gigantic civil engineering project and those are always late.
However, if you move to a molten salt reactor (cooled or fueled) you can significantly reduce the scale while still doing a 0.5-1.5GW plant. And you can use CCGT as well. This totally transforms the economics and while it would still a large plant it would be much more comparable to a gas plant in terms of capx. And in terms of opex the fuel should be significantly cheaper, while the labor required should be less in a modern plant.
The PWR real cost are the gigantic heat pumps and the huge required containment system. A molten salt reactor can be air cooled even in the desert of Arizona.
Hopefully in the future we can replace the CCGT with even smaller turbines like Super-critical CO2 turbines.
So I prefer large plants 500MW+ but they need to be molten salt cooled at least. My favorite design (for what is achievable in a reasonable time) is by Moltex Energy, the Static Molten Salt Reactor. Its basically the idea of filling the fuel assemblies with molten salt fuel rather then pellets and to cool you use another molten salt. And with some small amount of repossessing you can use current 'waste' as fuel. I think that design is of a scale and complexity that if some real capital got behind and government were willing to invest in their 'waste' rather then to drop it into a cave it could solve both the 'waste' problem and the grid problem.
Large scale is not inherently hard, the problem is lack of industrialization (lack of economies of scale). The "West" after the Cold War went all in on short-term-ism (both fueled by market liberalization, financialization of everything, globalization, plus as a consequence of all this the political gridlock that ensued).
There's also, honestly, the fact that full-size nuclear plants look threatening. They have an imposing size and shape, they dominate the horizon, they look like "if that thing blew up it would be catastrophic" (I know that's not exactly what happens, but still)
So as dumb as it sounds, just making the thing smaller might be enough to soften public opinion
Another reason to move to GenIV reactors, because once you don't need cooling towers. So if you design it right, most people will not even get that it will be a nuclear plant.
Its really the cooling towers that make it clear what it is and those look absurdly big.
Large scale plant construction is hard, takes a long time and the knowhow is disappearing (see recent issues in France with their latest project).
With a miniaturized plant the time to market is quicker, which hopefully will start having a positive effect on peoples opinions sooner when it comes to nuclear power.
It may not be optimal, but it has the potential of changing things for the better.