The fact Bitcoin is decentralized, it can't be possible for the government to stop it. Like you do said the government might try to stop Bitcoin those close to them not to buy Bitcoin but they can not stop the whole world from adopting Bitcoin. Bitcoin is free for everyone to own when they are ready to invest. Even some government knows the benefits of Bitcoin in the future that's why they have legalize it in their country but still few developing countries I think have adopted to the Bitcoin technology yet. The fact Bitcoin always fluctuate is what makes the government not to be comfortable with it. They can not control the price of Bitcoin as they control their fiat currencies.
The adoption rate isn't what it used to be then. Bitcoin might stick around, but its price could drop as demand falls. It's like that privacy mixer, if the government bans it, most people stop using it, even if a few die-hards keep it going. Similarly, Bitcoin could end up being used mainly for transactions instead of as an investment since its value isn't expected to rise much anymore. And, many miners might lose out because the rewards won't be as valuable.