I'm somewhat a prepper too, though I don't have much BTC. I don't think BTC would survive long against a major catastrophe.
I'd rather own valuables and bank accounts in several different countries. If something bad happens where I'm currently staying, I can just move elsewhere and keep on living the way I'm used to.
This is true. Things like electricity and internet access will likely become more scarce in the event of most doomsday scenarios which will push up the cost of both. The higher cost of electricity (and to some extent internet) will make mining less profitable, in addition to the fact that the lack of internet access would make bitcoin very difficult to spend (which is what ultimately gives it it's value)