I think the reason why other ban crypto because crypto is a new currency, unstable, highly fraudulent and has not reached a certain balance like some other markets such as stock, gold .... Governments have not recognized crypto to protect people against scam risks. Once crypto is more transparent and stable, I think it will be recognized and become more popular.
The government perspective is the reason why it is banned. Government tends to disloke crypto because of its nature. Just like its decentralization, also it is uncontrollable. That is what the government do not like. They want to take incharge to things that will help the economy to rise. They wanted to have the role in everything.