no one or no government can ignore or suppress the power of united people, if majority starts using Bitcoin now and often, any government would be forced to comply with the people's demand and legalize it. Also, the smart countries are already going along with Bitcoin and cryptocurrencies. and in a couple of decades, the world economy will be completely crypto-based.
United we stand, divided we fall. You are very right about this. It is not possible for the government to stop the majority from doing something. Bitcoin has a big support of public and rich people. Above all, there is no real logic to ban Bitcoin. Authorities have to describe the reasons behind their actions.
What would they say? That they illegalized Bitcoin because they cannot control it or it is not regulated. Also, it is impossible to stop someone from using internet the way he wants to.