"Not the Republicans" did not work in 2016, and won't work now.
Trump is obviously deranged and evil, but the Republicans like that.
The Democrats seem to hate their core values. In particular, Biden needs to stop quoting Republican talking points. No, the border isn't "broken". Yes, Gaza is a genocide.
Trump offers a pack of lies, but if you believe those lies, it gives you hope that things would be better in the future. And things are pretty shitty for your average American, particularly if you are in the 50% poorest. That is why "America is already great" bombed so badly in 2016, and why Biden is trailing in the polls: because he offers no hope for change.
Obama promised Hope and then Change, and delivered neither. He was America's last chance, squandered. Had he delivered for America, particularly the poor, Trump would be some bankrupt ex-billionaire. But at least he promised a better future.
When I first moved to America in the early 80s, socialized medicine seemed right around the corner. Four decades later, it is not even mentioned - even after the worst pandemic in a century.
Also, the fact that the Justice Department -- executive branch! - has been so incredibly sluggish at enforcing the law on powerful Republicans is a massive fuckup.
Here's the point where Americans tell me, without proof, that taking years and years to bring a case to trial is positive.
No, it isn't. No other country does this. The Constitution contains the right to a speedy trial. The fact that it is quite likely that the next election will be over before Trump's trials are, so he can pardon himself! (also not a feature in most countries) is horrifying.
My wife and I left America for good in December 2016. And let me be blunt: we worried we were overreacting, but things turned out a lot worse than we feared for America. (And I have socialized medicine again.)
The DNC needs to get its collective head out of its collective ass. They need to get back to their left-wing roots and promise a better life for Americans, particularly the poorest 50% who have been systematically shit upon by Reagan, Bush I, Clinton, Bush II, Obama and Trump.
I have had multiple American friends die in the street of exposure (example), and a couple I can't find and I suspect died. One guy simply got pneumonia and died from sleeping rough in LA and he wasn't crazy though Scientology had drained his bank account and left him homeless; the others had serious mental health issues that they were unable to get treatment for.
America is a cruel and desperate place unless you have money and almost everyone knows that. Until the Democrats start to fight actively against that, their prospects are dim.