They aren’t compared against each other, that’s the entire point. For progressive voters Trumps policies don’t matter because they’re not voting for him anyway, the only ones that matter are Harris policies. Likewise for conservative voters Harris policies don’t matter, she isn’t getting their votes. The ones Harris had to convince were the progressive voters and she spent her entire campaign trying to convince conservatives that she wasn’t that progressive.
The fact Harris lost is literally the only proof necessary to demonstrate her policies weren’t good enough. If they were she would have gotten more votes.
You seem to have things completely backwards. It isn’t the voters responsibility to vote for a given party or candidate unconditionally (even though in practice that’s exactly the way Republicans operate). It’s the party and candidates responsibility to convince voters to vote for them. When a politician loses an election, barring complicating factors like gerrymandering and voter suppression, it’s the politicians fault. Full Stop.
Then unfortunately the fascists will keep winning. You don’t win over people by telling them if they campaign hard for you then things will be just a tiny little bit better than they currently are. It’s the motivational equivalent of “Some of you may die, but it’s a sacrifice I’m willing to make”. Just look at the voter turnout numbers this election, they were abysmal. Trump absolutely stomped Harris, yet the total votes cast for him were still only a tiny fraction of the total eligible voters. Only ~65% of the population voted. That means if Harris could have inspired a portion of that 35% who stayed home to get off their asses and actually vote she could have won instead.