“Super expensive” for who builds them, or "super expensive" for the end user paying their electricity bill?

Also, there are safe solutions to store nuclear waste. They are not 1.0e31% secure, but many other kinds of power plants carry significant risks [1] [2] [3]

[1] https://en.wikipedia.org/wiki/Vajont_Dam

[2] https://en.wikipedia.org/wiki/Farmington_Mine_disaster

[3] https://en.wikipedia.org/wiki/2010_Connecticut_power_plant_e...

It's either expensive to the person paying the bill or to the person paying tax to subsidize it.

That's what "super expensive" means.

And yeah, most of it comes from the cost of building them. But they are barely competitive with solar + batteries if you count only the costs of operating them.