The point is why should someone get progressively taxed when they are attempting to live a "median" American lifestyle.
That is a home, a bedroom for each child (etc as the CNBC article pointed out)
But that's the point. If the median experience, in absolute goods is a certain thing, then why should someone making 6x the median income not be able to afford such a thing. And more topically, why should we introduce additional progressive marginal decrements to what they are able to have?