Not OP, but we have contractors in Nigeria, and paying them via regular bank transfer is nearly impossible. For example many banks will outright refuse to make SWIFT transactions to Nigerian accounts.
This is just one example of a few factors that lead to a sort of isolation from international banking.
Am not the author of that comment, but the fact that comes to mind is that aluminum is used for virtually all transmission and distribution lines - for price reasons - even though copper has better conductivity.
If we did discover a room-temperature superconductor, I suspect it would be a while before the cost to produce it in the bulk quantities required for electrical transmission are economically attractive compared to what’s already available.
This is just one example of a few factors that lead to a sort of isolation from international banking.