The government confiscating all your cash in a time of financial turmoil however... that's pretty much guaranteed to happen.
If they had wanted to be truly innovative... the card would not be a Mastercard, but a Bitcoin hardware wallet,
where the user would have to program it with their Public/Private key pair, and each citizen would be given at least
three... one pair of e-cards primary/backup, and a paper document that could be used to prove ID in order to replace
documents in case the other two were lost, so they could carry the first, lockup the second someplace safe, and put the third in a safety deposit vault.
It's Africa, the later 2 likely do not exist for the majority of citizens. I went there a few years back and it changed my entire world view. The people are poorer than you could possibly imagine compared to the US. You could be literally dieing in the street and nothing could be done for you. Fall out of a tree and no-one you know is around? you're screwed. (I actually witnessed a man die in this very way) But despite that incredible poverty, everyone has a feature phone with built in calculator, messaging, calander, etc... which, unlike the US, they actually use to run their lives. They barter with cellphone minutes, transferring money via their phones. Completely homeless people rent slots in cinder block buildings to run shops off their phones selling whatever they could find to locals and tourists alike. I felt great despair and overwhelming hope for humanity all at the same time.