Unfortunately for that argument, the vast majority of white wealth is not in the hands of the middle-upper class, and I highly doubt that the wealth of the 1% (or .1%) is mostly in homes and land inheritance. And if you're counting "middle-upper" as 80-95%, I think the top 5% has ~70% of the total wealth in the US... (for reference, 95th percentile is ~2.5m, or comfortably above your 500k-1m baseline. 1m is 88th percentile, 500k is 80th)

(And in any case, my point was just that it wasn't shown as causation in the stats you cited)