Before PIX there was TED which worked normal but you usually had to wait up to 3 hours to clear the transfer. Now because of the offload caused by PIX every single transfer you make through TED takes up to 10 minutes, usually 2, but noone cares. The look of happiness people have when they scan qr-code is the same of that kid that just got an ice cream. The reason why Pix was adopted so rapidly, and is so omnipresent, is because of ease of use. You scan the QR-code and that's it, transaction completed. Nobody mentioned that half of users is unable to figure out how to get started with pix, that is register keys, so they ask some techie parents, friends or go to the financial institution to get them started. Before most people that were inept to type in few necessary numbers to complete a transfer from one bank to the other, now switched to Pix and all they have to do is give the phone number or tax ID and are ready to receive money or scan qr-code to sent it out.
Because of that there is a total inclusion and also utter surveillance. So now in Brazil there are 2 problems, 60-80% of financial transactions are processed by the government and to add to the damage the entire economy is run on one point of failure which is WhatsApp. If at the same time, 2 of them would stopped, let's say for 3 weeks or maybe less, entire COUNTRY would do down the drain.
All the alternatives are fading away, lots of people don't even know how to change a ringtone on the phone but know how to do everything through WhatsApp. Try to ask, not even demand, in random business to provide you with alternatives for contact, you'd get that look saying GTFOOH. If pix would stopped, people would not go to atm to withdraw money, they'd wait until it'd come back online. When WhatsApp stops for few hours it feels like Sunday morning before the picnic.
Government+meta=success story of Brazil