If "banning" bitcoin really meant saying that exchanges can't let you turn dollars into bitcoins and vice versa ... could that finally make bitcoin an actual cu

If "banning" bitcoin really meant saying that exchanges can't let you turn dollars into bitcoins and vice versa ... could that finally make bitcoin an actual currency, where to get it you exchanged a good or service for it? Would the disconnect from the rest of the financial system mean that it wouldn't just be a vehicle for speculation? I still think it's a silly system, where an extravagant amount of work is done so no one has to trust any central party (but all the speculators had to trust the exchanges). But I wonder if "banning" it could be the thing that actually lets it fulfill a little more of its original promise.