I don't understand your response. I asked why we are assuming these voters prefer Harris over Trump and you responded by saying that their preference for Harris is irrelevant, because they don't want Trump.
This doesn't make any sense.
"don't want Trump" in this context MUST equate to a preference for Harris over Trump. And my whole question is "why are we assuming these voters hold that preference?"
Well, don't get me wrong, a WIN for a 3rd party IS the ultimate goal. But change happens slowly in politics and in life. Slow and steady support for a three party system will eventually result in that end. Continued support for a two party system, by contrast, never will. I, myself, will continue to place votes for the better of those two eventualities.