Case in point - UK's latest nuclear power plant has been delayed and costs literally billions of pounds more than planned because hairline fractures were discovered in the reactor containment vessel. That sounds bad, right? Anyone who hears "nuclear containment vessel" and "fracture" immediately goes into panic mode and hence why the amount of money being spent on fixing this issue is literally unlimited and the entire project will be massively over budget in every possible way.
But......other nuclear reactors in britain(and in fact across the world) operate with the same fractures in their vessels and it's not considered a reason to shut them down. It's an inevitability of the manufacturing process, the vessel is still strong enough to withstand any kind of situation it could conceivably end up in, so it's literally nothing. But because it "sounds" bad the British public are spending billions to improve something that doesn't need improving, because like you said "Nuclear requires perfection". And I don't disagree with you in principle, but I think we have to acknowledge that perfection has a number of degrees to it.
This should be viewed as "corrupted regulators" rather than "magically strong materials".
In 1986, the Challenger blew up. We learned that although originally good safety standards had existed, over time a series of small exceptions had been made, each one on the theory that "hey it never blew up yet, a small change won't matter".
Reactor licensing works like that. Sure, the reactor vessel is cracking which was never expected to happen. Sure, the graphite bricks are cracking which was never expected to happen. The important thing is, it never blew up yet, and that means it's perfectly safe to ignore the problems.
At some future point there will be a Problem and it will be dutifully explained that a series of small deviations from safe practices became normalized, blah-blah, and everyone will nod and take the lesson to heart, until it happens the next time.
Or you know, the fact that some of these reactors have been operating for close to 50 years and are fine is proof that it is actually indeed fine.
I don't know - would love to hear an expert argue either way.
If you answer "zero chance" for all of those answers, you're being unreasonable, and choices like that increase the radiation you'll be exposed to.
The rules that require perfection are not there because of actual risk. We're past the point where things are already so safe, and releasing so much less radiation than coal plants, that getting stricter just makes the world worse.