If anything this seems to support the position that the only way to reduce costs is to increase volume. A classic economies of scale example. Instead the experts want to disregard the data for vague reasons.
Economies of scale generally exist, but it’s not magic. A large fraction of construction costs for nuclear power plants is very similar to other structures. A high pressure steam pipe is a high pressure steam pipe and people are constantly building structures using them.
By doing international standardization and coordination in ways similar to the aircraft industry, the same should be possible for the nuclear power industry.
It should be possible to consolidate most of global production down to a handful of companies (like Boing and Airbus), with a forest of subcontractors in the same way that was done for airliners, and achieve similar economies of scale.
Successful designs could be re-used over a period of 20 years or more, with only minor modernizations of things like electronics, like the Airbus A320 or Boing 747.
Ideally, we should have done this in 1980, but even if we start today, nuclear can provide a lot of energy at very competitive prices in the next 60-100 years. By then, we should have fusion or the ability to build energy storage cheeply enough to make renewables (probably solar) competitive.
Finished airplanes can transport itself by flying. This advantage is particular to aircraft industry and probably can't be copied by other industries. Finished buildings can't transport itself.
Most are things like reactor equipment, turbine equipment and electrical equipment. I'd bet most of that could be built in a central factory, and then shipped to the site.
In fact, when comparing to air travel costs, the reactor buildings can be compared to the airports.
Starting nuke construction now would just be kicking the can down the road again.
Economies of scale is more of a fixed saving on top. This may have helped take the cost per kwh of solar from $10 to $3, but the scientific development was what made it possible to go to $0.1.
In any case, PV prices are already very low. We are reaching a point where installation and maintaince are becoming limiting factors, and where storage is becoming the primary bottleneck.
Development in storage (batteries and hydrogen) already has so much momentum that building out some nuclear power would not threaten it.
New PV tech, like perovskites, might carry prices down further once the learning curve for Si levels off, but we are not there yet.
There is no "storage bottleneck". We just don't have anywhere near enough renewable generating capacity to justify diverting capital from expanding it to building storage. Diverting capital to boutique nukes, and to coal while we wait a decade or two for the nukes, would be far, far worse than that.
When we do start building out storage, vanishingly little of it will be batteries.
Why yes everyone should consolidate global production of _nuclear power plants_ to a handful of companies probably based in the Western world.
Imagine if there were 200 operating systems for phones, instead of 2? How would corporations know which were safe enough to install 2-factor auth on?
Imagine if there were 200 suppliers of x86 cpu's, all with small differences in features? How would we build safe software for those?
Consolidation to a few vendors (but more than 1) is a huge benefit for both costs and safety.
And there is absolutely no reason these companies need to be "Western", unless you include Korea, Japan, Taiwan and India in the "Western World".
China would probably have one such company, but would perhaps only be trusted by their allies, just like US companies would probably not be allowed such infra in China or Russia.