If that was really the case why don't say JPMorgan and Wells Fargo enter in a partnership to provide such service?
If it's really cheaper, faster more convenient then they'd be enthusiastic about doing it because it would look good for their bottom line.
Money at the end of the day represents trust.
If the Fed is the most trustworthy entity then JPM and Wells Fargo are at #2 and #3. Nobody would care if the #2 and #3 institution exchange money between each other instantaneously and 24/7/365 but only settle their accounts at the Fed weekly or bi-weekly.
This thing for everybody to have an account with the Fed in the form of tokens (digital dollars and digital euros) is something really strange and that nobody has asked for. It is the project of some beurocrat which has seen a topic of interest among the population (crypto) and wants to look good to his superior or wants to claim that "I was at the helm of the team which developed the Digital Dollar".