At least single issue voters do vote for the candidate who supports their single issue. Anyone in the Abandon Harris camp who voted for Trump because of the Biden/Harris handling over the Palestinian genocide was severely ignorant of Trump's policies. I guess this would have to include those who didn't see him as a threat for their interests and decided not to vote.
It'd be like an anti-abortion single issue voter casting a ballot for a candidate who's supporting Extreme Abortions ™.