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.
We all know that cryptocurrency is the new modern currency which can transfer money easily and instantly. The reason why they ban it is they can't control this currency simply because of its being decentralized. Cryptocurrency has no tax and I think it is also reason why they banned it. Lastly, I think they certain reason why they banned it but I do believe they will recognize the real use of cryptocurrency in the near future.