Really doubt that rational, decent people will accept an unsolicited call from a stranger and then discuss their personal politics with that stranger. They just don’t answer or hang up. The polls are structurally flawed. Also pollsters know how to please whoever pays them.
Some are, some are not. I formerly participated in Zogby’s polling. It was internet based. I used to get a poll every week. It would ask me about 10 qualifying questions. In addition to political questions, there would also be questions about other random things like which peanut butter do you prefer, etc.
It always asked me IF I voted in the last election, who I voted for. If I planned to vote in the next election. Then socio economic questions on income, location in suburbs, married, children, etc.