Point well taken. I should have probably said, don't watch primetime TV or something? I agree though, the medium isn't at fault. Tons of good stuff on TV if you hunt around.
TV is a medium for entertainment, and entertainment is subjective. How, when or why you consume it, as long as it isn't hurting anyone, shouldn't be up for judgement.
Maybe, better advice would be, to stop watching tv when it is no longer providing you the benefit you were seeking. Like, turn off the TV when you aren't enjoying watching it anymore and find something else enjoyable to do.