Not sure why this is so complicated --- blame the DNC and party elites, not the population that voted for Trump.
If the DNC was trying to win, they would have never let Biden run for re-election, and then they would have never let Harris become the candidate without a primary.
The Democrats literally told the US population Trump was going to destroy democracy in America, and then created a situation that enabled him to win in a landslide.
The Democrats didn't lose because Harris didn't get a primary. Literally no one but Republicans who would never have voted for her to begin with cared about that.
Democrats lost because they keep triangulating and trying to appeal to centrist Republicans who either don't exist, or would never vote for them regardless. If Harris had distinguished herself from Biden by taking a firm stance against the Palestinian genocide - which was the single issue much of her base cared about - she would have won.
Also, Trump didn't win in a landslide. It was a close election, and Trump definitely won the popular vote, but the margins were still about 51% to 49%.
Supporting your argument:
From a left leaning publication
https://www.bostonglobe.com/2025/01/12/opinion/opinion-renee...
And from the WSJ (I don’t know how the paywall bypass works. I pay for Apple News and read the entire article).
The WSJ is right leaning when it comes to business. But I find it to be fair and not Trump worshipper
https://www.wsj.com/opinion/bidens-bitterness-came-back-to-b...
When it all comes down to it. Biden was no better than Trump. They both are old folks who put their own desires above what is best for the country.