It's my understanding governments have considered light-touch regulation of nuclear safety with the policy "any nuclear power plant that can get insurance to cover a $100 billion+ meltdown cost can be built" and the result is nobody can provide such insurance, so no plants get built.
There's an actual actuarial analysis online somewhere, though I can't remember if it's in German, and the problem is not population size, but a nearly unbounded risk. Take a look at Fukushima and think about what would have happened in terms of cost had the wind blown in another direction.
