I think that the quantity I offered suggests why there might be a correlation between inequality growth and (r - g), independent of the mechanisms that underlie

I think that the quantity I offered suggests why there might be a correlation between inequality growth and (r - g), independent of the mechanisms that underlie the returns on capital and labour, and inequality. In words, when r > g, the income distribution tends towards the capital distribution, and when r < g the income distribution tends towards the labour distribution. The relationship between this point and meritocracy is that average returns on capital are approximately "unearned" - you can get close to the market rate of return with minimal effort, whereas returns on labour are positively earned, by your labour. So when r < g the limiting case is for income to match labour, i.e. effort. Note that this by no means inhibits the possibility of greater returns to intelligent capital investment (something that you definitely want to keep) - the point is that you control average returns to stop capital domination fostering inequality.