I guess I'm confused by your take then, and the evidence you use to support it. You stated "But you move up in your career just like everyone else does" from a 65-75K starting salary as a college grad, when your own figures show that the average household income is oftentimes comprised of two people making even less than that, but have reached the stage of upwards mobility to buy a house, albeit oftentimes "house-broke" and in strife to pay mortgages.

These people didn't move up, as per your assessment. Most people need to combine salaries with someone else to even have a fair chance in this system, to get any upwards mobility.