Nuclear reactors take a long, long time to recoup the investments. During that time the cost of electricity generated by them is quite high compared to renewable sources like wind and solar.

This compounds when cheaper sources are being added to the grid, pushing prices down and making nuclear even less viable economically. For nukes to work, economically speaking, electricity prices need to be stable over a long period of time or they become perpetually in the red.

For this to work you can't have liberalised electricity markets, you need the government take the brunt of the risk of new nukes when it's economically not viable and have a design that spans a lifetime of 50-70 years so future generations can benefit from the lower cost after the capital costs are paid off.