The name is just passed on to the issuer to confirm. Most will only look if the transaction is suspicious and I believe right now, Monzo outright ignores it. You could write literally anything in the name field and have it accepted. Let’s also ignore that most cards are lost inside wallets with other cards or a form of ID, even if that ID is just something like a named Railcard.
The reason names are not on cards is because they’re produced in large batches and shipped to Monzo HQ before being put in to envelopes or handed out in person.