Lets assume that starting in USA all bitcoin to fiat exchanges are banned. Will people be still interested in Bitcoins? I believe the applications of the blockchain are many, however, most people are attracted to Bitcoins because of its fiat value (or USD value). Deep under I believe that people are really not interested in the use of bitcoins in a decentralized platform/application but more interested in converting Bitcoins in to USD. Fiat currencies still seems to be the norm. Any ideas ??
If Bitcoin to fiat exchanges will be banned in a country of course some people will lose their interest on investing on it because it will be hard to trade it for fiat and if caught selling or buying you might get jailed. However, selling Bitcoin is not limited to a country so you can still sell it in other places that allows selling of cryptocurrencies. I also think that way, people are not really interested on using Bitcoin for paying something, most people just want to invest in Bitcoin because of the huge profit that it can possibly return to them. But we can't blame them because it is hard to find any use cases yet, and mass adoption is not yet achieved.