I completely agree with everything you said except for ONE little thing:

You are grossly misrepresenting how far that can is kicked down, for the worse. It doesn't kick it down a couple thousand years, it kicks it down for if DOZENS of millennia assuming we stay at the current energy capacity. Even if we doubled or tripled it, it would still be dozens of millennia. First we could use the uranium, then when that is gone, we could use thorium and breed it with plutonium, which would last an incomprehensibly longer time than the uranium did. By that point, we could hopefully have figured out fusion and supplement that with renewable sources of energy.

The only issue that would stem from this would be having TOO much energy, which itself would create a new problem which is heat from electrical usage.

Some of the biggest blunders of all time come across because too many people let perfect be the Nemesis of good

I really cannot stand that phrase because it’s commonly used as poor rationale for not favoring a superior approach. Both sides of the debate are pushing for what they consider optimum, not “perfection”.

In the case at hand, I’m on the pro-nuclear side of this. But I would hope I could make a better argument than to claim my opponent is advocating an “impossible perfection”.

Why is it supposed to be easier to get people onboard with nuclear (which is decreasing) than wind and solar (which are increasing at triple the rate of the nuclear construction peak in the 80s and growing at 20% p.a.)?

People are on board with VRE. Some of the are on board with nuclear too, but it's not working.

Buying time isn't a great argument for nuclear when it takes so much longer than wind or solar to build a plant - median time of 88 months to build a nuclear plant compared to 8-14 for solar.

People will get on board when they see the cost per kwh.

The problem with Nuclear's "good enough" is that Nuclear is currently worse than other technology we have in almost every way.

1. Higher total lifetime cost per kwh than solar or land-based wind (and hydro, but that's niche), even after factoring in capacitors for weather and time of day/year
2. Awkwardly front-loaded TCO. You basically pay a huge percent of that ugly TCO up front, making Nuclear more prohibitively expensive than its modest total lifetime cost would imply.
3. Long life. This is a terrible thing. TCO's of solar and wind plants are predicated upon a 20 year obsolescence. That means, the TCO includes the cost to build, tear down, and make way for the inevitable better tech in 20 years. Nuclear plants are priced at 50+ year lifetimes. You can't easily retrofit a nuclear plant with better technology if/when it starts to catch up.

It is absolutely true that solar and wind are better because more money has gone into their research. But because of that, they are better options in almost all real world power situations.

The problem with focusing on nuclear is... why waste all that political capital just to spend 100x the money or more that you could spend to be 100% renewbles in the short term? The front-loaded TCO is the real issue with that one. If you wanna hit 0 emissions tomorrow with Solar/Wind, you're just paying the up-front costs, knowing there are per-year costs (still cheaper than fossil fuels) to keep it going. If you want to do the same with nuclear, you're paying for almost all of it out of the gate for 50 years worth. Suffice to say, that's a budgeting nightmare.

And what's left is space. Nuclear creates a lot of power in a small area. But wind and solar are both far more easily/efficiently integrated into the space we are already using.

But this is my argument against those who complain about Solar and Wind -- those won't kill you or destroy a location for hundreds of years if they break down and once they're installed they don't have to be fed by more mining, or anything else. Just wind and sun.