Bitcoins operate off central Banks meaning the government can not control its supply or influence its value like they do with fiat currencies. This threatens their ability to manage national income. Also since Bitcoin can be pseudonymous, the government worries that people may use it to evade taxes, launder money,Or finance illegal activities.
Why are some embracing it while others seek to regulate or restrict Bitcoin??
Simply because, not all people aim to get freedom from the government, from the fiat dominance where value depreciates in the long run.
While those who wish to get rid of banks and centralized government, they'll surely embrace bitcoin because it could be the best possible way to be with their own bank and to stay anonymous no matter what.