Afraid I have a slightly different view on Norman Lear's "contributions".
I loved All In The Family and a lot of his other shows, but the advent of his influence was a definite demarcation of a shift in culture that I personally find detrimental. He didn't cause it, but he definitely poured gasoline on the fire.
Before Lear's shows conquered the airwaves, TV sit-coms at times showed the foibles of men as the head of the family, but by and large they were still given respect as the head of the family (Jackie Gleason's 'Ralph Cramden' notwithstanding - he was definitely more the exception than the rule and he and Alice had no children, so . . . ). We went from "Father Knows Best", Andy Griffith, Ward Clever and others that showed the father of the family as hard working, caring, compassionate, wise, loyal, and loving even when his mistakes or handling of the situation was fodder for laughs - Lear gave us the pattern that started with "All In The Family" and unfortunately remains to this day where the father is the dumbest, most incompetent, clueless individual in the home and is more stupid than the smallest speaking child or even the dog at times and is mostly racist , bigoted and or totally out of step with "popular" culture.
It's like "dirty" jokes among a lot of guys . . . we laugh at it because we find it funny to our baser instincts, but used to be it was in poor taste to tell such in mixed company and especially in front of the kids - these days it's 'award winning entertainment'. To me I see the results of it as the coarsening of society - lack of respect for each other, common decency and manners, young people , actors, athletes and especially women (supposedly 'role models') who speak publicly in ways that would have made a 1940's sailor blush . . . to a lot of people it's just a 'sign of the times'.
Just so. And that saddens me.