I'm not familiar with venmo and zelle, but from what I've heard about them, debit cards in the US sound like they're not much better than credit cards.
Venmo and zelle are two apps that allow instant p2p payments. Venmo was first; zelle is the banking sector's answer (a whole bunch of them got together and agreed to support it). Both are widely compatible; zelle has no transfer fees. That sounds just about as good as anything else I've heard of in NZ, and it has the added advantage of having an external competitor (venmo) pushing the banks. In other words, not everything is under one roof, and I believe this will actually drive innovation in the long run.
I'm not familiar with zelle, but I know venmo (and competitors like Cash app) take a business day to transfer the money into your account. Or they can do it faster for a fee.
> debit cards in the US sound like they're not much better than credit cards
the are all better than paper checks
I don't doubt it, but in many countries, paper checks already died out a long time ago, and credit cards aren't really catching on for anything other than online purchases abroad, because we already have better solutions for most of the things they do.
As an American I write exactly 4 checks per year. Two for county taxes and two for town taxes. Both have a credit card option I can use, but it's through a third party that charges extra for it.