LogFAQs > #896724617

It's kind of leveled off the last few years because it couldn't get much worse, but prior to these last few years, it was on a steady decline for 2 decades.

By far the biggest culprit is the rise of "reality" tv. Even on the History Channel of all places, now it's almost non-stop Ice Road Truckers, Pawn Stars, Axemen, etc... Yeah, when it was "the WW2 channel" it was bad too, but at least that was actual history, and they did sometimes deign to broadcast other topics.

24 hour news also rose to massive prominence to the detriment of us all.

And the third worst thing to happen to tv is the latest bout of prudishness, particularly when it comes to sexual topics but other areas as well. This seems to have started around the time of the 9/11 attacks, and I've read pretty interesting articles linking the two events. It started w/ the religious right, and the sex-negative left is taking up the fight with gusto now.
Just sad when you watch a sitcom from the '90's and amidst the joy, you repeatedly find yourself thinking, "damn, they'd NEVER be able to say/show/do that on a tv series that came out today!"