> GDP/capita aligns very closely with material standard of living for the median person

GDP is an average, not a median, so it might align with the average person, not the median. The average/mean can hide many things (see Anscombe s quartet) which is one of the problems with GDP IMO.

It depends what you’re using the data for. If you’re comparing across countries, or looking at a developing country over time, it’s a relatively small factor. The ratio between the average and the median isn’t that big even in the U.S. (about 1.3). Meanwhile, Poland’s GDP per capita has tripled since 2005: https://data.worldbank.org/indicator/NY.GDP.PCAP.CD?location....