Ultimately, any of the stablecoins on Ethereum will have to be in compliance. The entities that issue them will have to register, most likely as a bank, to be able to operate.

i would say that this applies to traditional entities such as a corporation, but what happens when it's a DAO that operates the stable coin? Seems like that would still be possible on Ethereum and would be decentralised. i suppose that the DAO would still need to hold the assets backing the stablecoin in a bank or via treasuries, somewhere.

It's going to be interesting and HBD being at the base layer is certainly a benefit to Hive.