He was nominated by the Greenback party, (third party) running against the Democrat and Republican nominees. He had less than 1% chance to win according to his wiki. I’d say that no matter how fuzzy the definition of major party is, the Greenbacks weren’t that.
He sounds like he was an intelligent person who was concerned with social justice, especially for the native tribes.
Democrats have been concerned with his age, it was being taken seriously, hence the calls for him to pass the torch. I think his age was being taken seriously. While he was the presumptive nominee, he would have had my vote because I believe Trump should never ever be allowed to serve again. I’ve said I’d have voted for a dead frog before I’d vote for Trump and that wasn’t a joke.
I don’t think it’s hypocrisy to support the candidate you have been given, until he isn’t the candidate any longer.
I do see your point; I believe that it is the perception of many outside the Democrat party.