If this was during the infancy of the internet, bitcoin would've already died since we only have a single server on a single computer way back then. But we are lucky to be alive in the age where we have multiple servers that not only offer connectivity, but security to bitcoin as well. So unless a massive asteroid hits the planet and threatens all life, I don't see how bitcoin would die off due to disasters.
Natural disasters must only occur in a few countries, it is unlikely that earthquakes will occur simultaneously throughout the world, while those who use crypto are people all over the world, so crypto will not be affected by it
I get your idea and I am in agreement with it, though I would like to correct you regarding your claim that only "some countries" experience calamities. For all I care the whole world experiences disasters, no one place safer than the other. It's just a matter of timing.