In my opinion, authorities avoided regulating this space because they already have a precedent. They convinced Bitfinex to use multi-segregated wallets to store

In my opinion, authorities avoided regulating this space because they already have a precedent. They convinced Bitfinex to use multi-segregated wallets to store customer funds, and this resulted in the Bitfinex Hack. My guess is that authorities are probably keeping too careful when it comes to regulation.