it will be very difficult to make bitcoin as a currency because if the government has not legalized bitcoin it will not be able to make bitcoin into a payment tool, which is still the issue that is legality
if on a government scale, I think that is indeed quite difficult, because many regulations are not appropriate. however, when many people know how to use bitcoin, I think you can still do that on the internet. basically the use of bitcoin is indeed unlimited as long as it's not illegal for you.