the promise of ethereum is you can shrink middlemen and rent seekers down to zero or almost zero in many cases. And in every case where you can, you should. zero-trust, no-fee immutable contracts can be considered an amazing "public good".
If I were a bank, why would I want one guy at the top that I have to trust not to empty the accounts because he fell for a nigerian scammer? It's a corporate liability. If you even still need the bank in the first place.