If BTC became used, is hard that govs or bank can stop them. Stop bitcoin should mean stop Internet, and them can't do that.

So how can be accepted by govs and banks? Maybe in the future a good compromise will be forse the transaction not from address to addresses (like public key) but force people to open their "new" bank account on platform like the actual Coinbase.

Transaction will be checkable by govs and banks and a lot of theyr problem will be solved.

The new "black market" will be the "Coinbase off transactions", it will be the new tool for tax evasion.