This can obviously not be the entire fraud prevention mechanism:
> Zelle simply "implemented a mechanism that allows banks to claw back funds from the recipient's account and return them to the sender."
I'm curious to see what the prerequisites for such a clawback are, both on the side of the payer (a police report? a signed statement? a click in an app?) and the payee (what happens if the money isn't in their account anymore?).