Why do pro-Trump people keep wasting their efforts haranguing Republicans who do not want to vote for Trump, even though their votes would be meaningless?
Yes, that's right: meaningless.
As I keep trying to tell you people, there simply aren't enough GOP voters left to elect anyone. Republicans compose about 25-27% of the electorate, and are disproportionately spread among relatively low-electoral vote states. Do the math.
To win the Presidency as a Republican, the candidate needs the votes of Independent voters in a few key swing states (OH, PA, VA, NC, FL), and to hold on to all of the states that McCain and Romney won, and that's where Trump is falling short.