The limitations discussed in the parent post come from a clearing system that must (for legacy reasons) support payments via cheques. There are many payment sys

The limitations discussed in the parent post come from a clearing system that must (for legacy reasons) support payments via cheques. There are many payment systems which don't do that (e.g. SEPA credit transfers in EU, and various other 'giro payment' schemes), and can do fast and cheap payments that are actually known to be fully cleared right after receiving them. The key thing for preventing money-forwarding scams, however, is that all the commonly used payment systems in your society must be "reliable". If some are, and some are not, then the intersection of these payment systems opens people up to an "arbitrage" of sending "reliable money" after receiving "unreliable money"; you won't eliminate this type fraud by making a better payment system accessible, that will happen only after systems like cheques are driven out.