This is a good question and I think the clues are in the way informal vendors in parts of Asia and Africa have already caught on to transacting through mobile. In remote parts of ES there aren’t any bank branches and villagers have to travel an hour or more by bus into town just to open an account, when they get back to their village that same lack of infrastructure means no POS or businesses accepting cards. Feature phones and smart phones, however, are ubiquitous and this gives an “official” way of doing this.
This solution doesn’t have to be crypto at all, however. I’ve been to China where even food carts have QR codes printed on them for people to take wechat pay and ali pay.
Electronic transfers are common. But electronic payments like that are not so much.
We have Bank QR codes and something simillar to M-Pesa, but its not that widespread because there is no one standard for QR payments or similar. That makes it less practical to use because both you and the vendor must use the same bank. (El Salvador is small and there are many finatial instituions.)
Something like U.S. Zelle or Swedish Swish would help, but banks have not standardized yet.
If WhatsApp started something like WeChat payments it would become a hit. Like they did in Brazil.
You presumably live in a developed economy. There's a reason 70% of El Salvadorans don't have bank accounts, and it isn't a context of easy online banking.
It's small payments what are are mostly done in cash, like the $0.20 bus fare, $1.25 lunch, $0.50 soda or $0.25 tortillas. There is no widespread electronic alternative for those payments yet here.
Free mobile banking accounts have been available for a while in El Salvador, and can be opened with a selfie and a photo of your national ID. They are only avaialble for those 18+ and older though.
