Just like the tendency to blame the "white working class" for Trump's victory. In actuality, the white working class was under-represented among the Trump voters.
Why did these centrists supposedly all defending "reason" go down that rabbit hole? Maybe it is and was too painful to recognize that business as usual and dynastic entitlement (and "lean in" feminism) is not what the US needs right now. What it needed at the time was Bernie Sanders.