[refurb]

One edge case? Look at the debt levels in the US! There is a huge chunk of the population that has a negative net worth, mostly due to mortgage debt.

Is it fair to say all those people are poorer than people in India who have a few dollars to their name?

[smallnamespace]

Well, show me a perfect metric that doesn't have similar edge cases?

For example, income has its own issues -- a retiree can have little income but a big retirement fund to draw down.

In an ideal world, you'd probably measure something like current net wealth + discounted expected future earnings, and maybe use PPP instead of GDP, except now you're trying to measure two things accurately instead of one, and making guesses about the future too.