If Government is not in support of bitcoin it can affect bitcoin, especially how to spend bitcoin. It will be rare for people to accept bitcoin as payment to buy somethings , maybe only those who are bitcoin lovers will accept bitcoin for payment. When government is not in support of bitcoin, bitcoin will be used just for investment mostly.
It happens in my country. You even cannot use Bitcoin for payment purposes at all. No one braves enough to accept Bitcoin because the laws don't allow it. If you try to pay for any goods or services with Bitcoin, you may be in trouble with the laws. In this situation, Bitcoin adoption for payment purposes is deadlocked (no way to try). The only way to use Bitcoin is for a digital asset, it is allowed. According to this situation, sure it is very clear that the government has a crucial role to speed up Bitcoin adoption.