I don't think that math works out, even when looking over the entire 70+ year life cycle of a nuclear reactor. When it costs $35 billion to build two 1MW reactors, even if it will last 70 years, the construction cost being amortized over every year or every megawatt hour generated is still really expensive, especially when accounting for interest.

And it bakes in that huge cost irreversibly up front, so any future improvements will only make the existing plant less competitive. Wind and solar and geothermal and maybe even fusion will get cheaper over time, but a nuclear plant with most of its costs up front can't. 70 years is a long time to commit to something.