You probably don't know anything about the war. And I wish you will never know what it is.
If there really will be a Third World War ..... Well, I don't think that the Internet at all will be or electricity in general. If people are refugees, very often they lose (in fires, shelling) even documents that prove their identity. I'm not sure that everyone will be able to take with them passwords or portable wallets.
During the war, real estate, cars are depreciating, inflation is growing by a million times, I don't know about cryptocurrency, it can in principle depreciate greatly, or, conversely, the price increase & it becomes a unique asset.
It's so scary, I can not even convey it to you with words. We all need to pray that this does not happen.