I’m not sure why you are spending so much time comparing nuclear to coal based plants. If you wanted to make a compelling argument there you’d need to compare it to renewable energy sources. I totally agree that we need to phase our coal based plants as fast as possible.

Because Germany decommissioned their Nuclear plants before they did so with coal plants (or gas plants, which they keep building)

The price for the fuel isn’t so much the issue but availability or rather dependency on outside powers.

Sure, but price is a function of availability and demand. The price is low because it's pretty available and the demand is nothing like that of oil, LNG or coal. Plus Canada and Australia have some of the biggest reserves in the world (3rd, 4th) and they are western democracies we can rely on. Also, Uranium isn't bought JIT, but it's bought years in advanced so that it can be enriched and stockpiled, this means that it doesn't feel the price fluctuations that much.

I’d much prefer the option with less reliance on other states for our power sources.

As for renewables, I don't know if you've noticed, but most solar cells right now come from China, if they were to stop selling tomorrow (for one reason or another) we'd be kind of screwed anyway. Maybe a good mix and diversification is the best answer here. And yes, I know that you don't need China to keep operating your solar cells, but they are kind of needed right now to make the transition, new cells will be needed to replace old ones, and we also need batteries, which they are now leading production of. Unless we move manufacturing back (which we should do, but that's a decades long process we can't possibly rely upon) we are still reliant on an external state to undergo the ecological transition.

I have yet to see a convincing strategy to explain humans in a few thousand years what we buried in these tombs. It just doesn’t seem plausible. And even if we find a few suitable places are we sure we will find more when those have filled up?

Maybe it won't really be necessary, some 4th gen nuclear reactors promise to be able to use spent fuel for their reaction (also Thorium, which is extremely more abundant than Uranium). These are now like fusion reactors, which are permanently 20 years away, but we are building them right now. Some of these plants will go online this decade afaik, and if they deliver, many more will surely follow next decade.

Using spent fuel should shorten the estimated containment time from tens of thousands of years to 300 years, which should be enough to just say, bury them and leave.

The delay and cost is definitely subject to policy and policy changes. But today no-one can guarantee that we wont do those and in effect have a delayed and very expensive project on our hands. I’ll remind you of Stuttgart 21 or the BER or any other bigger projects Germany has been dealing with as long as I can remember. I have no faith that a reactor would magically be built without any of the issues those projects have.

This is an issue we might be able to fix without hoping for magical technology. Also because it doesn't touch only this argument, but pretty much everything happening in the country. We can't just say "Germany can't make any big project" and leave.