Sure you could look at capital investment as a form of payroll, but it's going to heavily skew the numbers and now GDP is not a great way to estimate if we can afford to pay a livable wage simply by looking at GDP.
Your right, numbers don't show everything and yah just can't redistribute gdp in a communist sort of manner. But I do think one of the parents thinking exercises does indicate that wealth distribution is more of a problem in America than certain European nations.
Capitalism for all it's flaws is a great system to motivate work, wealth creation, and capital investment(as u mentioned).
In an alternative reality fairer system that can muster up a similar work ethic the average person would be better off and you'd have similar innovation potential but with different work ethic driving motivational mechanisms. But that's a improvable hypothetical to be fair. That's your point of contention right?