I think the only lesson that Democrats can learn from the past three elections is that women have no chance at presidency. If anything, as an outsider, the campaign Harris led, seemed to reach vastly more people than Biden's.
I am 100% convinced a Republican woman could win. I was in touch with a lot of deep-red middle-of-the-country Republican voters and candidates for state and federal offices when Palin was the VP pick. Shooting-stuff-in-political-ads sorts. It was practically all they talked about. They liked her a ton better than McCain. I think they’d have gladly voted for her at the top of the ticket (granted, they lost that one, but I think an R woman could absolutely be elected President, probably more easily than a Democratic one).
That would be missing the forest for the trees in my view. I could see it having an impact, but when 60% of people say that the country is headed in the wrong direction, putting up a candidate who was in power the last four years just isn’t going to work. Biden would not have won a primary, and neither would she have