Kamala's participation and enthusiastic support for the ethnic cleansing of Palestine was a significant factor in her losing. As was her enthusiastic support for border militarization and conspiracies about illegal immigrants.
She dug her own grave. We were told to shut up whenever we mentioned how unpopular those positions are with anyone who's not a far right nationalist. She drove millions of voters away from her by being a neoliberal conservative. This outcome was entirely predictable.
Can't speak for everyone. For me it's cause there are kids out there who didn't ask to be born into this and who will suffer greatly because of it. I can't abandon hope if it means stepping aside and letting the world do whatever they want to them.