Blaming the Victims
It’s kind of victim-blaming bullshit that people are more angry with people who want to vote their conscience and choose the most progressive candidate than with the assholes who are hell-bent on installing a fascist dictator in the White House.
You really should just let the process play out as it’s meant to instead of haranguing people because this is exactly what the primaries are for. Telling people they’re being stupid isn’t going to do your candidate any favors.
And if you think someone who is voting their conscience can be persuaded to “be pragmatic”, then you are utterly and hopelessly optimistic about human nature.