This is a little outdated. Most banks finally got Zelle setup this year. It hasn't fully caught on but you can get free transfers between nearly all big banks and a lot of small banks simply by setting it up and knowing the persons email or phone number. I've been trying to get my friends to move off Venmo, but the option to do it is usually buried inside of the banking apps so it isn't as convenient.
It's still not quite the same. In Germany, Australia and NZ, you can send money to anyone at any bank, for free, and you don't need to use their phone number or e-mail address. It's mandated by the government.
It'd be more like the Federal Reserve enforcing free customer-to-customer ACH for everyone. There are some banks that do offer free person-to-person ACH (I believe 5/3 is one of them).
Zelle is basically the banks getting together and going around that critical lack of infrastructure. It does look like they have a lot of major and minor banks. Mine is still missing from the list though, and I suspect it will be years until everyone is supported or banks will feel they need to support it to enter the market. So no, the US is still way behind.
