As a point withiin the greater whole, I don't think that the security requirements of photovoltaics are the same as those for a nuclear reactor. Also, security difference between "spent" photovoltaic cells v. spent nuclear fuels?

In any case, the overarching point: "you wouldn't believe the amount of nonsense that can be disposed of simply by looking up the relevant numbers and doing a minute's worth of easy arithmetic." turns out to not be so simple, because there are a lot of issues involved. There's the issue of disposal, which you show a link to, but you don't seem to have incorporated those numbers. There's the issue of how much taxpayer money goes into scrambling jets near Indian Point each time alerts are raised, etc.
The calculation clearly isn't easy in the present, and also does not incorporate the cost/benefits analysis of focusing on photvoltaics because ultimately they will almost certainly be more efficient (your efficiency/production rates for existing infrastructure doesn't reflect changes and advances in technology, of which there are many).
In short, "easy arithmetic" isn't always so easy.