And how would their people acquire this “wealth” in the first place?
Oppressive regimes tend to control money flow in/out of the country. So if you, for example, have an aunt somewhere outside that wants to send you money -> you just might not be able to receive it, or would need to give some official a slice of the pie. Bitcoin obviously can help as u can just move the money without government oversight.
Acquiring this "wealth" of crypto would be impossible in an oppressive regime in the first place.
There were actually a few news articles about people in 3rd world countries that survived thanks to btc, though I can't find any at the moment.
Lots of people do person to person transactions.