There is so, so much that couldn't air today. All in the Family could never air today. I used to love that show when it was on late nights and realized that it could never work today because it's too complex - Archie had his negatives, but the show always tried to show that he was basically a decent man who loved his wife and child while still harboring regressive ideas. Today, you could never show it (unless you make it incredibly black and white, bigot vs. progressive type of thing).  Hell, Blazing Saddles couldn't get made today due to it's racial humor.  And Friends would get protested due to all the Fat Monica jokes they had.