Brazil's government-run payments system has become dominant

Sweden has had a similar system for several years before PIX in Brazil. It is also integrated with the digital ID system (BankID). The main difference is that the Swedish system is ran through a private organization managed by all the major banks (and the central bank) in conjunction. So the central bank doesn't have direct access to the transaction data technically.

While the Brazilian system is only interacted directly through your bank application, the Swedish application is a separate application tied to your bank account in the backend. Given the... quality of bank apps this is a huge plus. The Swedish Swish app is MUCH easier to use because it only does one thing. My Brazilian mother does not know how to send PIX because her bank app is very confusing and the PIX option is just one of many.

The BankID system of Sweden though is even more impressive than money transactions, pretty much everything government related (including healthcare, taxes, etc) and most private institutions (bank apps, Swish, digital contract signatures) is done through the unified BankID login.

People raised concerns over privacy, but the main problem really is that since these systems cut out the middle man (Visa/Mastercard) and have no fees you also have no fraud protection which is something to keep in mind when using them. Once you send the money it is gone, the banks will not give it back to you even if you got scammed. It creates a whole sort of scam industry in both countries.

https://en.wikipedia.org/wiki/Swish_(payment)

https://en.wikipedia.org/wiki/BankID

This is the difference in Brazil. Because it's ran by the Central Bank, there are some fraud protections. For example, if you receive money by mistake, you have the option to return a transfer to the original sender. And if you don't do that almost immediately, the sender can actually sue you and get the bank to revert the transaction (once proven you've deliberately chosen to not return the money).

There are also other security features tailored for the crime aspect of Brazil (since some people argue Pix increased the number of flash robberies); you can limit how much money you can transfer via Pix during day and night time, and even request a second confirmation before the transfer actually goes through. And if you prove you've been robbed, the bank can easily revert the transaction and you can get your money back.