See people aren't exclusively machines.
I know people who felt that both sides at least tacitly supporting the genocide was so depressing that for their mental health they basically checked out of politics.
No, that response isn't helpful, but it's a very real thing that happens to real people. They needed a candidate that cared that people's lives were ending across the sea, and neither side offered that.
That hurt Kamala's chances in a very real way, and might even be the deciding factor for Trump's second term.
While you and I can look at this and go "Wow, that's not logical, she's way better than Trump", the Democratic campaign should have had political scientists and psychologists that knew about this well-documented phenomenon. I imagine they did, and ignored it, because siding against Israel would've cost money.
So while it's true that the choice was still objectively obvious, it's also completely true that the Democratic campaign absolutely mishandled it, because this isn't some new phenomenon, and group human psychology isn't unpredictable. It's also not the fault of those who didn't vote because of that.