You call my question funny, but at the time his viewpoints were probably very commonplace among the general populace who were older than 40. Having a character with those views was only groundbreaking because even then the television studios in California were much more PC than the general public across the country.
I think it would be WAY more groundbreaking today to have that show than it was in 1970. TV could never have someone as a main character who espoused views like Bunker’s today.
ETA: I suppose rightwing views were much more prevalent back then... but, if that’s the case, why was a character on TV with these views “groundbreaking”?