Part of the reason for the election spectacle is to make people feel invested in their decision to vote for whoever they do. If you vote for someone and they get elected, then any criticism of that person is a criticism of you and your decision making.

People were fine with criticizing both Biden and Kamala during the 2020 primaries, because they weren't invested in defending their decision, but the moment he became the nominee, he became a shining pillar of perfection, and as soon as he was no longer the nominee, he lost that. It almost gives you whiplash how quickly they switch back and forth between stanning everything he does. I've also seen the bullshit talking point of, "Congress controls weapons sales to Israel, Biden would love to stop it but can't because he's just a smol bean" (ignoring all the times he bypassed Congress to send more weapons) suddenly disappear from liberals' mouths. Seamlessly, they've switched over to BlueAnon conspiracy theories about how Kamala is secretly pro-Palestinian and is just pretending not to be to fool ~~the deep state~~ Zionist voters, or just willfully misinterpreting her statements as pro-Palestinian.

No propaganda could ever compete with what voting does to people's brains.