If I’m not mistaken, the highest (or second highest) number of bitcoin transactions occur in the African continent and even despite the technological differences you mentioned they seem to be quicker to understand and adopt bitcoin when compared to “westerners”. There may or may not be any correlation around child mortality specifically but in sure we agree and can see that the quality/strength of the money affects most if not all of these factors in some way. But yes it’d be incredibly difficult to parse out all the data to support this theory. On a gut level the theory makes sense and for this mental exercise that’s good enough!