Another possibility is that the US simply isn't building as much these days, and heavy construction might have lost economies of scale. The Baumol Effect is another possible contributor. Renewable construction is not of the same kind, especially PV.

Specific construction expertise for nuclear very likely has degraded (the US can no longer forge the large reactor vessels for PWRs, for example.)

Nuclear is going to be further negatively affected if there's a transition away from fossil fuels, since the industrial infrastructure for making steam turbines will no longer have as much support. Bespoke turbines from smaller makers will be more expensive.

Building out transmission lines for low-intensity power sources like wind/solar is labor intensive, like nuclear power plant construction, so I suspect factors like the Baumol Effect similarly affect the cost of both.

Nuclear plant construction has the potential to become much less labor intensive if it moves to smaller, standardized nuclear reactors that can be manufactured in factories, using mass-production techniques.

>>Nuclear is going to be further negatively affected if there's a transition away from fossil fuels, since the industrial infrastructure for making steam turbines will no longer have as much support.

True. However this is a surmountable problem. It's just a matter of using subsidies to achieve economies of scale in nuclear plant construction.

I am skeptical of the SMR-built-in-factories schtick. It sure isn't helping NuScale control costs -- they're up to $15/We now, and it will not be surprising if that goes even higher.

The problem with the subsidy argument is there's no good experience to show that subsidies would do more here than just burn money. Nuclear has not had good experience effects. This is in sharp contrast to renewables and storage.

Nuclear is weighed down by the boat anchor of its historically poor performance.