Well, they would have to do what PayPal did, which is build
1. A system that is acceptable by the regulations of any possible country they want to operate in.
2. Implemented by as many merchants as PayPal is.
This is feasible but not trivial.
Now, if you add in the "defy governments" part, it's clear that most merchants would not use it, which means users have a negative incentive to use libra over PayPal or whatever.
Even Amazon and Google failed to "just build a PayPal", and I don't see why Facebook would succeed easily.
This is feasible but not trivial.
Now, if you add in the "defy governments" part, it's clear that most merchants would not use it, which means users have a negative incentive to use libra over PayPal or whatever.
Even Amazon and Google failed to "just build a PayPal", and I don't see why Facebook would succeed easily.