There were three pillars in the Obama coalition.
1 was minorities.
2 was women.
3 was millennials.
The big problem was millennials, who need 'inspiration' to turn out. Who turned sullen when they didn't get the candidate they want.
So ask yourself if there was anybody that could have satisfied them? Apparently not the first female president, because everybody loves the ideas of hard work and resilience until it comes with 'bad optics'. Everybody loves experience and consideration until it comes with "not a good look". Everybody loves the idea of diversity and making history, until it comes with a woman who has made history so many times in her life.
Everybody sure loves making compromises with white people now, but they didn't like it when Hillary Clinton did it.
Because they wear their respect for the American values of hard work, resilience, understanding, and diverse experience in their mouths, until time came when this was actually on the ballot against the antithesis of all these things, then they didn't like it so they didn't turn out. They would prefer charming old white man.