Maybe you're confusing the terms "income" and "disposable income"? The latter would presumably include the items you mention, but the former does not. The (unreferenced) numbers you cite are almost certainly income, not disposable income. Or perhaps you're assuming that all costs have increased only by inflation, which is not true.

Median housing cost in 1960 was $11,900, which was about twice the median income at the time. Today it is nearly $400K, which is over 4 times as much as the median income. Medical and education costs have similarly risen faster than inflation (and faster than wage growth). You're right that it's not that complicated, though.