What if World War 3 breakout ?
Do you expect bitcoin and other cryptocurrencies to go down in price ? As people will swtich to hard cash or gold?
Note : There are wide power outages, servers getting down, no electrictiy and everything bad you can expect if WW3 happens
If World War 3 will happen(i don't hope it will) the Bitcoin and other crypto currencies will drop in rate because like you said it most people will use cash or gold.
And you actually answered yourself if the servers get down people can't use the Bitcoin.