The time to vote for someone good is the primaries, which set what the dichotomy of the actual election is going to be like. In the November dichotomy, voting for the lesser evil is kinda the only option unless you want Big Evil to win.
Yes, it would be better to "merge" the main election and primaries into a ranked-choice vote but that's not happening anytime soon.
Yes, which is why voting is not enough: you have to campaign for the candidates you want to see. The ranked-choice system would fix this but that's off-limits for now.