If a country bans bitcoin then the mining difficulty will adjust and the hashing continues elsewhere. Much like other p2p networks, Bitcoin is a borderless hydra that simply cannot be stopped.
Rather than take it offline, another possibility is to size the hashing power and use it to undermine the currency.
Energy consumption is a large red target making it easy for nation states to attack.
I cannot easily target your computer running proof of stake in your closet.
I can easy to cut the electrical wires into your proof of work data center.