I think part of the problem is the tv studios just don’t have the time for high def cinematography. They are cranking out shows every week, and using standing sets over and over again. Sometimes redressing them to substitute as another location. i.e. a dining room gets redressed as a bad guys office. Costumes are another issue. They only have a few days to design and make those costumes (dresses). They looked ok on a standard tv. HD reveals just how quickly they were thrown together.
Switching out the cameras and editing equipment is only half the job. The hard part is producing content worth watching in HD. Go out on location and shoot in the Grand Canyon. Spend weeks shooting when the light is perfect. Now you have something worth watching in HD. You’ve also spent a small fortune doing it. That kind of shooting schedule is impossible for a weekly tv show.
HD shines for sports and television content with very carefully planned cinematography. If I’m watching Castle and for example, there’s a shot of Beckett and Castle talking. HD doesn’t really matter imho. A talking head looks just as good on my 1995 Sony. yymv I’m sure kids that grow up watching HD would be jolted by a vintage 1995 Sony.