what happens when the telecomms infrastructure is hit and shuts down? or when there is no power?
I imagine it would be a lot more convenient to have some hard currency at hand when fleeing a conflict zone. One might need to bribe border guards at some remote location with unreliable (or non-existent) internet connection, to get to safety.
Both are quite valuable tools to defend oneself. They have different balances between risk, convenience, liquidity, anonymity.
Because that is essentially what has happened now with the SWIFT sanctions.
Cutting off internet from outside world is much more drastic measure, highly unlikely to happen for a prolonged period of time.
Even if it does happen, you can still use telephone lines to connect. [1] [2]
[1] https://www.dw.com/en/european-activists-offer-dial-up-inter...
[2] https://www.france24.com/en/20110201-speak-to-tweet-egypt-tw...