This appears to highlight the need for the sort code and account number to be prominent (either in the app or on the card). Give that Monzo is an app only bank, the need to make sure that people have the details to hand should be addressed. I wonder if these details could be introduced to the customer on the welcome letter perhaps.
While we are increasingly living in a world where everything is done by a touch of a screen (or soon just looking at it), surely Monzo exists to making banking easier for people now as well as into the future?
Wider discussion about the sort-code and account number issues here: Add Account Number & Sort Code to the Debit Card