Thank you for bringing up this data point! I'm sure we both agree that's a much better argument than "trust me" :)

I understand, however it was a disclaimer not a "trust me". One of the main reason such metrics are not as reflective of the reality is that for developing countries, the taxes are not reported accurately. A lot of wealth is officially unreported - and it is a massive amount. Such things are not captured by official statistics, by virtue of being unreported income, which leads to an incomplete or distorted picture of reality.