I think there is no chance that governments would ban bitcoins. Most countries including USA, gains a lot of taxes from bitcoin profits. Why would they stop such an earning? besides I think that most fund companies and investing companies invest and trade cryptocurrencies, they would not accept such a ban. All they like is fud and fomo
I agree to some parts of your discussion that the govt is enjoying the heavy amount of taxes from the bitcoin or any crypto investor but the real fact being the unknown source of the cryptos, by unknown I mean the mining or exchange of cryptos aint controlled by any govt organization can cause huge trouble to the countries economic stability, thus the govt may not totally ban bitcoin or any of the crypto but they might impose some kind of rules to keep a check on the usage of the cryptos.