By the numbers nuclear is very safe but it does have asymmetric risk and most importantly a bad reputation. Next gen nuclear should be a marketing rebrand in addition to new tech. So Yang is right to focus on thorium.
Charity often does good, but often does not have the intended or apparent result. See William Easterly on the subject.
Yes.
You are only looking at the immediate damage. After the dust settles, with a worst-case nuclear accident you have a heavily contaminated area which cannot be resettled for a long time; after a worst-case hydroelectric accident, you have mostly only water and mud, and can start rebuilding almost immediately.
That's only with modern risk-avoiding-at-all-costs safety standards. The initial plans for handling Chernobyl, the worst fallout nuclear incident, was to cleanup - which they did - and resettle soon afterward the cleaned up area - which they did not. And now we have that useless extended exclusion zone - a monument to giving in to our fears.
Those plans were made before the incident by medical physicists. They were then modified by the party to suit political realities on the ground. Even the authoritarian URSS knew how far it could push people.