You can’t use “we survived the cold war without nuclear war” as evidence of anything. Because of the anthropic principle, we could have blown up the human race in the 1960′s in 99% of all possible worlds and you’d still be born in one where we didn’t.
FWIW the main reason you can’t is that odds are nuclear war wouldn’t have “blown up the human race”—there’s plenty of ways it could have had several billion survivors. So, if it had been near-inevitable, that’s the kind of world where we’d expect to be in, whether you take anthropics into account or not. By that standard, you wouldn’t be able to use the Green Revolution as evidence of anything either (it probably saved roughly as many people as the lack of a nuclear war during the cold war did)!
Likewise, I think the prevalence of supernumerary nipples in humans is probably severely underestimates because probably the vast majority of people who have them mistake them for moles