Actually, I'd like to expand upon that "why men are portrayed as idiots", and what I've come to feel:
In the '50s, TV portrayed the ideal family. A strong, supportive, bread-winning father; a nurturing (if sometimes prone to overstep her bounds) beautiful housewife and mother; and a few scamp kids. This was the idealistic portrayal of men and their family. They were, as the saying goes, king of the castle.
But I still think, to a degree, TV portrays a fantasy life. Rather than having a super dad and father, he's average. He's fat, he's slobby, he's lazy, he's not terribly bright--and yet he has a smoking hot wife (who also makes money now), a gorgeous house in a gorgeous neighborhood, lots of friends, and a comfortable income (even if he works for a low-paying menial job). He usually isn't very affectionate or caring for his family, and yet a single act of kindness will remind his family that, really, despite all his faults, they still love him. He slacks off at his job, but you'll only occasionally get an episode dealing with a job crisis (then everything is back to the status quo).
This is another kind of "idealism". A kind where the man doesn't have to work hard, be affectionate, can sit around and watch TV and drink beer, and yet have a wonderful life. The worst thing that happens is occasionally bratty kids and a nagging wife.