Talking about "the economy" being good is counterproductive, and Biden never learned that. Because it doesn't matter how good "the economy" is on paper, if the billionaires have the vast majority of the money the rest of us are fighting over scraps.
We all know where the blame belongs for that: Manchin and Sinema. If things like wealth and windfall profit taxes could have been passed, if the child tax credit hadn't ended, if price gouging could have been banned, if a national abortion rights law could have been passed, if the court could have been packed, if the fed could have been coerced into not screwing with interest rates, if "return to office" policies could have been banned, if a national "housing first" for homeless people could have been made law....
And of course if Biden could have stopped supporting genocide, Kamala would have gotten the votes anyway.
But the reality is that the economy stinks. Not because it doesn't look great on paper, but because of how few people actually benefit from it. Wages stagnated again, union membership stagnated again, and campaigning by trying to blow sunshine up our butts was a stupid idea. It's obviously broken, it obviously needs to be fixed, and if your campaign is telling everybody that it's great, you're screwing up.
It's going to get worse now, of course. Because as bad as the center-right Biden and Harris are, the right wing extremists are far, far worse. You're definitely going to be worse off in four years if you're not already insanely rich.
All she had to do to win was commit to ending arms shipments to Israel. She wouldn't do it. Lots of people who cared about ending the genocide stayed home.