If one day, BTC enters our daily life!
The government can use BTC to replace the current legal currency for economic activities!
Businesses and individuals also have to pay taxes, but change from the legal currency to BTC!
I think the Government is afraid of losing taxes, maybe one day bitcoin and alt coin holders have to pay taxes.
I understand this as a concern, and this is why some countries still forbid crypto.
If everywhere will take the bitcoins the government will have nothing to fear. Let's say the restaurant started taking bitcoin. The license to work for this restaurant is issued by a government agency. And the owners also pay taxes to the state. Also, a certain amount will be included in your restaurant bill which will go to pay tax. That is, the country, in any case, will receive income.