Considering about 45% of the country is about to vote for a literal fascist and racist who opposes the first amendment, I think it's a pretty valid statement.
Trump won the primaries because he had a plurality of the vote in the primaries. He wouldn't have won without our undemocratic FPTP system. Yes, the party got behind him later, but that includes people like Paul Ryan, Rob Portman, Marco Rubio, John McCain, Chris Christie, Ted Cruz, and others who would undoubtedly be "superdelegates" in your ideal world. Anyway, even if Trump was supported by a majority of voters, the idea that you can simply get rid of political views you don't like by preventing them from voting is cute. Maybe the PRC can get away with it, but they're an authoritarian dystopia that isn't what we want to emulate here, as much as many American political hacks would like to.
Anyway, I'll go through step-by-step everything wrong with your plan in a second.