I don’t see that as such a threat any banning just means you push-up the price as people pay more to get a hold of it and then have an asset they can use without government control
Yes you’ll need fiat to pay for things but that can be done on the settlement later level so you only convert what you need to buy and nothing more!
Will it make it harder for users yes, but not impossible! At this point however with companies, banks and countries owning it I doubt bans will come in!
If it happened here I’d take my crypto and move and think nothing of finding a place thats crypto friendly