There are a lot of issues with your post imo.

First, cash is going away, soon. Sweden has done it years ago. Europe is now playing catch up.

Second, a universal digital currency will remove all system heterogeneity. Yes money is already digitalised, but across several proprietary environments. I can and have set up several accounts across several banks so my spending cannot be fully tracked by a single corporate entity. This will be moot once everyone has to use the same harmonized system.

Third, one of the sponsors of the universal European currency has been caught talking about time limited digital currency. As in, spend your money or it just disintegrates after a set amount of time. Which really destroyed a lot of trust in the endeavour

They’ve been around a bit now. Everyone seems to be pretty satisfied. Desktop app could use some improvements, which is already on their roadmap

Money transfer platforms are even worse than chat apps in terms of how acceptance dictates usefulness. You might convince a couple of friends to use xmpp instead of whatsapp. But its near impossible to get major outlets to integrate new payment methods. Especially if that platform advocates privacy and therefore doesn’t offer a return on invest based on user data. I don’t think we’re gonna see true alternatives without government regulation, and even then…

“Can I please use your phone?” and then just start scrolling through their texts and pictures