Well, there certainly are banks in the US that don't, and why are apps like Venmo a thing over there if the same thing can be done already? =/
I guess it's because of the bank you chose, since the one my relatives use don't have any of that, and are those apps bank-specific? Do people not having your bank also receive the money instantly?
Most of the medium to large banks have that option. Many partner with Zelle because it is not bank specific, though I once had a credit union account that let me do ACH transfers to other accounts. But as you point out, there's also PayPal and Venmo. My Amex lets me split purchases by calculating the portion and sending PayPal or Venmo requests on my behalf. I think the largest difference may be that there's no one way to do a thing, while at least to me as an outsider, it feels like Europe has One True Way.
I guess it's because of the bank you chose, since the one my relatives use don't have any of that, and are those apps bank-specific? Do people not having your bank also receive the money instantly?