Nuclear is NOT liable for a major nuclear disaster. No insurance would cover it. So I don't know where you got your knowledge from but it is not based on fact.
Edit: OK I should have been clearer. They are liable like everyone else. They have (unlike solar installations I suspect) strict liability which means the damaged person does not have to prove fault. However, the amount of liability is limited (in time and amount) and the state takes over. This is what I was referring to with they don't have liability (admittedly incorrect the way I wrote it).
Source:https://world-nuclear.org/information-library/safety-and-sec...
The article you linked says that TEPCO paid out USD ~65 billion after Fukushima, but it was insured only for USD ~804 million.
Naturally what happened is that the government didn't want to be without electricity, so to prevent bankruptcy TEPCO was nationalized. This is the typical scenario for nuclear power: profits are privatized while losses are socialized.