Some people have different priorities.

Participating in the electoral process reinforces existing power structures. To instead challenge them, some advocate for direct action and grassroots organizing as more effective means of enacting social change. Some would rather build alternative systems and communities outside traditional political frameworks, because liberation comes from collective action rather than reliance on electoral representatives.

While I don't like legitimizing electoralism, and I would rather the billions spent on it go towards real tangible needs, I don't abstain, I do vote. So I can't fully defend this position.

Plenty of people who didn't vote probably honestly don't care, but that doesn't mean they actively want Trump. That's just silly to suggest

Some people are just apathetic about it, and a lot of those people likely feel that way because there's no mainstream candidate that actually seems to care about their needs.