Older shows had some time to find their footing with the audience to make adjustments. You have to consider relative to the budget if the show is too expensive it could be canned far easier and if the show has star power that could keep it afloat for another season. Today you have to jump out the gate with it being strong in quality and numbers. Seinfeld, Breaking Bad didn't start out with big audience viewership. It had time to grow.

Comedy is another issue, we kind of gone too far and rounded off the edges in comedy that it's perfectly too smooth and safe. Comedy can get dark, absurd, and crude all without having to go over in that Mature rating. It's like a gradient and when comedy doesn't have all the shades of color, we run into problems where now a normal person can tell easily something is off because they can foresee the setup and punch line when they shouldn't mostly. Comedy is still here, it's that TV comedy just got social neutered a little too hard trying to be too mindful of others that it weakened jokes.