My taughts:
There is little danger to the economy from banks serving as custodians and transfer agents for cryptocurrencies. Nor do I think that investment firms that make investments in cryptocurrencies for their clients is a risk to the economy
There are risks in investing in Bitcoin, and big institutions that are investing in Bitcoin for their clients are also taking big risks because they know that the price of Bitcoin can crash at anytime. So, it is a very big risk for them. And as for banks, I am not on support of banks handling cryptocurrencies. They have no business here, their only business is with fiat. That’s their business, though they can still choose to invest in cryptocurrency, that’s their own choice.
But having a bank here means that we are starting to turn this into a centralized body, and it will no longer be decentralized. We don’t need banks for any reason, not even for exchanging. We already exchanges, both the centralized and decentralized ones.