Well, you could invest a little time and find out who/what they are.
Or you could just go with your stereotypes and prejudices, ASSume no decent human being could possibly disagree with your political ideas, and dump the guy/gal.
Good Progs don't check their stereotypes and prejudices, as that puts one's entire worldview at risk. So ASSume & DUmp.
Most worldviews are like glasses through which one perceives and interprets the world. "Progressivism" is more like an airtight diver's helmet.