Even Mexico has SPEI payment network which costs $0.36 USD for any amount

https://en.wikipedia.org/wiki/Real-time_gross_settlement

TED in Brazil - instantaneous transfers between bank accounts, managed by the central bank. Cost from zero to 2-3 dollars per transaction.

Australia has the New Payments Platform (Osko to consumers) that is basically instant.

Just to add, if you don't need instant payments we also have other convenient and direct transfers between banks in Australia.

Canada has free “Interac E-transfers” that you can send to an email address or mobile phone number.

Historically most banks have charged $1-$2 for an e-transfer (often with a limited number of free transfers per month, or a different type of chequing account one can sign up for to get free transfers), though it seems prices have been dropping in the past few years. Apparently the Bank of Montreal removed e-transfer fees on personal accounts a year or two ago.

So there's definitely still overhead that can make small transfers infeasible, but it's getting better.

CIBC has done the same. TD charges only $0.50 on the most basic plan and it is free on other plans. Simplii (née PC Financial) has always had free Interac e-Transfers. Interac fees have vanished or are vanishing for most people. The daily and weekly maximums are still an issue though ($3k and $10k at most banks usually).

Almost all UK banks use Faster Payments, which means ordinary bank transfers are instant.

Serbia (not in EU) implemented instant bank to bank transfers recently

Sweden have a thing called Swish which has instant transfer to anyone who you the mobile phone number of. End users have no fees when using the system to transfer to each others. Businesses that use it pay some though.

It has gotten very prevalent.

SEPA ist anything but instant for me. A transfer takes a day most of the time

SEPA Instant Credit Transfer is a different thing than just SEPA.

SEPA Instant Credit Transfer should allow this, but it's adoption is not 100% widespread yet, in my experience.

For domestic bank-to-bank payments, China has CNAPS https://www.bis.org/cpmi/publ/d105_cn.pdf [PDF] - the paper (2012) could be updated especially in regard to foreign currency.

tl;dr CNAPS is a bank-to-bank system, but in effect means domestic CNY transfers between major banks should settle within 30 minutes.

WeChat Pay / AliPay are a bit different, more like PayPal (though not completely like PayPal).

PayPal?

Not really a bank-to-bank system; money doesn't instantly arrive at the recipient's bank account and paypal's ability to withhold it is notorious.

Nor is PayPal obliged to pay into deposit protection funds as EU banks are AFAIK. I think PayPal needs to start worrying about their standing in EU and becoming a collateral damage when France and Germany are on a roll to make a case for exercising currency sovereignty.

I'm fairly certain that PayPal is registered as a bank here in the EU, possibly in Luxembourg. It couldn't operate how it does here otherwise.

Most banks will charge you extra for the instant payment. It's pretty ridiculous.

You're a couple of decades behind the times as far as the EU is concerned.

There is a function called "instant transfer" in my Raiffeisen ELBA app, it seems to be free and fast. (In Austria). However, I do not know how other banks handle thism

Not in 3/4 of the world as of today.