Its a type of energy that gets more expensive
Hard to get insurance, so all costs fall to the states while all profits go to companies
Trash is not solved
A minor error can have a huge environmental impact, especially in densly populated areas like Europe
Plants need cooling, most use rivers and that does not mix well with rising temperatures, and have to be shut down in summer
No public backing
High initial costs, high costs so run, high costs to dismantle
Nuclear plants are not flexible and can't react to energy availability
Most fuel is produced by less reliable states. Renewable energy is produced in your home country.
No chance of decentralizing the grid, making it a target for single point of failures or attacks (State sponsored or terrorism)
Solar is cheaper, battery parks are cheaper, hydrogen is cheaper, wind is cheaper, hydro is cheaper.
All in all, there are cheaper ways to create and store more energy safely, more decentralized and with less ties to single big companies.
Money is no issue, because if we have billions to throw at one plant, we obviously have enough for a smarter grid with storage options.
Or, you know, invest in renewables, better international grids and sodium-based storage instead of bring fine with turning part of your country into a wasteland...