I was wrong about the election and wrong about what the American people as a collective value. I was wrong in ways that should have been obvious, looking back now.
A crucial part of my mistake was also Hillary's mistake - that there was no basket of deplorables. Which also by extension means that there was no basket of wonderful moderate Republicans ripe to be swayed to the left on social issues. They will always think of the left as just waiting for a chance to attack them too after whatever monstrosity the far-right puts forth is defeated. Yeah, it sure sucks about the way non-white people are being treated, but there's a zero percent chance I'll ever be mistaken for one of those! But there's a non-zero chance those oversensitive liberals might yell at me if I make an "edgy joke" about killing all the Jews, so better continue to side against them for my own safety! You will not reach these people by invoking empathy ever, no matter how far you "compromise" on the issue of treating minorities with respect.
You'll never reach a Republican by appealing to empathy - you have to go through their own wallets and their own suffering.
Another mistake was not giving people what they wanted to hear. No one cares about whether a policy is feasible or even reasonable - as demonstrated by the fact that we're building a stupid fucking wall just to show immigrants what we think of them. People desperately want something to believe in even if it isn't true. And it's not like we'll ever be held accountable for exaggerating if blatant lying isn't even checked, so there's no real disadvantage to promising the moon as long as we don't give too many uncomfortable details.
Hillary was too worried about people not thinking a plan is feasible and therefore going on to perform some deep multi-factor analysis to write up a series of books on how her plans wouldn't succeed due to some unaddressed factor. But almost no one cares even if someone does that, because they still want to believe. You have to give them something they want more, in which case suddenly the protective safeguard magically vanishes and suddenly the first plan can be actually criticized.
Just be vague and rely on infinite plausible deniability like Republicans do!