I can answer this in one word: privatisation.

The neo-liberal economy is at total odds with this industry.

For a private enterprise to succede at nuclear power, it would take someone crazy and with very deep pockets like Elon Musk, but even then, his model wouldn't work as failure is not an option. You can't fail and iterate.

So what we have instead is privately run nuclear power plants, that are entirely publicly funded, with 0 risk taken, in typical neo-liberal fashion: socialisation of the costs and risks, privatisation of the profits.