I think Carroll O'Connor's portrayal of Archie was to get laughs while making conservative Americans look bad...sort of like Steve Colbert, with the difference that with Archie it wasn't totally malicious. Maybe because "All in the Family" wanted a larger audience whereas Steve Colbert has a narrower niche he's aiming at.
Was Edith Bunker's maiden name Dingbat? Archie called her that all the time.
In real life Carroll O'Connor was more liberal than Rob Reiner.
But he too, was a hell of an actor.
IIRC, the highest paid TV star of the '70s, and worth every penny.