The income data I had stopped at 2016.
The median home price in 2000 was $165,300; 3rd quintile topped out at $42,233 and the 4th quintile topped out at $65,653
$165,300 / $42,233 = 3.91x median household income
$165,300 / $65,653 = 2.51x median household income
The median home price in 2007 was $257,400; 3rd quintile topped out at $49,968 and the 4th quintile topped out at $79,111
$257,400 / $49,968 = 5.15x median household income
$257,400 / $79,111 = 3.25x median household income
The median home price in 2016 was $310,900; 3rd quintile topped out at $59,149 and the 4th quintile topped out at $95,178
$310,900 / $59,149 = 5.25x median household income
$310,900 / $95,178 = 3.27x median household income
The 2018 median at $328k may be proportional to the 2018 median household income, but in any case the current multiplier is way more similar to the one from 2007 than the one from 2000.
Not to mention other segments of inflation that may be outpacing incomes, such as health care or food or energy. IRL, how much people pay for housing is usually determined as the residual after their other expenses.
My point is that I don't think home prices can get that far out in front of incomes.