It's true that a pound of nuclear fuel costs more than a pound of coal. But it also has a million times more energy content, which is why fuel is only 15-20% of the operating costs compared to >60% for coal. And that's for legacy nuclear plants designed to use moderately high enrichment rates, not newer designs that can do without that.
> Nuclear must have a more complicated boiler setup with an extra coolant loop.
You're describing a heat exchanger and some pipes. If this is the thing that costs a billion dollars, you're making the argument that this is a regulatory cost problem.
> You need shielding and equipment to move spent fuel and a spent fuel cooling pond.
Shielding is concrete and lead and water. None of those are particularly expensive.
Equipment to move things is something you need at refueling intervals, i.e. more than a year apart. If this is both expensive and rarely used then why does each plant need its own instead of being something that comes on the truck with the new fuel and then goes back to be used at the next plant?
> Insurance isn’t cheap when mistakes can cost hundreds of billions.
This is the regulatory asymmetry again. When a hydroelectric dam messes up bad enough, the dam breaks and it can wipe out an entire city. When oil companies mess up, Deep Water Horizon and Exxon Valdez. When coal companies just operate in their ordinary manner as if this is fine, they leave behind a sea of environmental disaster sites that the government spends many billions of dollars in superfund money to clean up. That stuff costs as much in real life as nuclear disasters do in theory. And that's before we even consider climate change.
But then one of them is required to carry that amount of insurance when the others aren't. It should either be both or neither, right?