An NFT is a mathematical process. How you gonna ban it?
Dude have you ever tried selling or buying an NFT? My guess is no.
The protocol is a mathematical construct but the real world implementation relies on a slew of third parties, any of which can be shutdown by governments across the world.
NFT rides on the backbone of crypto blockchain, most notable the ethereum blockchain. While this is decentralized in theory, in practice no one is running a full node and no one is mining their own coins, people buy through exchanges, and exchanges can be shutdown by governments.
Most NFT storefronts require sellers and buyers to sign up with a wallet, such as metamask, which again means its another chokepoint that is ripe for government intervention
Not to mention these storefronts themselves can be shutdown, sure you can say whats big deal just run a TOR orion node, except TOR is a US intel/navy project and we all know what happened back to Dread Pirate Roberts and his Silk Road 2.0