The problem with pushing payments is that the cost of fraud falls on the payer. In the pull model, if the payer says it was unauthorized, the rules favor the payer--restoring the payer account happens as a matter of course, and disputes are handled subsequently. This sucks for the payee, but they're usually businesses who are more sophisticated and better placed to handle these issues. But in the push model, the presumption is the payment was intended by the payer. It's a wholly reasonable presumption assuming sophisticated, rational agents. But we're talking rolling out push payment systems where the payer will be your elderly grandmother.

It won't be pretty unless there are some aggressive changes to existing regulatory and legal frameworks. But it's not easy to figure out to protect consumers in push payment systems without opening gaps where fraudsters can directly abuse the system, like checking kiting scams of old. (Checks are a pull payment type of system, but the important point is that the cost of check fraud--forged, kiting, etc--fell primarily on banks and merchants, and less on individual grandmas who couldn't buy food because they were stuck in a months-long battle with the bank to recover funds.)

Zelle has a limit on the amount I can transfer, especially for new contacts. And it is precisely new contacts where I need to make a big payment, latest example being the contractor to remodeled my kitchen and didn't want credit card payment for some reason.

Zelle isn't run by the banks, it's operated by Early Warning and it's a scam service designed to harvest everyone's bank transaction history for intelligence gathering and fraud detection services

https://www.earlywarning.com/