I haven't had television for over 30 years (although for the past few, my husband and I do have a small set dedicated to watching videos a couple of times a week). We don't feel culturally detached – we do listen to public radio, which has wonderful programming and news – we keep informed about almost all modern culture except TV actors' names.
The year I left the TV behind was the year I left my first marriage behind. The tube had been on almost 24 hours a day for years, and I could hardly endure the constant background noise. My daughter was about eight, toward the end of a school year, and at first she was upset not to have TV. Every few days she'd come home from school and beg me to get a television. I'd distract her with projects, picnics, trips to the library, and she'd be okay for a few more days.
Then we had a summer break away from most of her school friends, and she stopped asking. We were having an awful lot of fun. Spending time in nature. Having great conversations over board games. Reading good literature together. It really was idyllic. When the new school year started, I still didn't hear anything about getting a television. Until a few weeks later, when she came home and complained that her friends never did anything interesting – they only talked about television shows. YES!
She still scarcely watches TV, and so far has kept her 4.5yo son away from the tube, though they do watch a kid's video once in awhile. My grandson is very up-to-date on superheros and the more popular kids' toys because he hears about them at preschool and has "heroic" underwear. And he hears cultural references all the time in conversations with the many people in his life, including his own parents. Plus we have the space to introduce him to classical culture, upon which many more current references are based.
The single most wonderful thing about getting rid of commercial television is the lack of commercial advertising. It helped when I was a single mom bringing home barely more than minimum wage that my daughter wasn't begging for all the "latest." And nutritionally, it was easy to keep soda, sugared cereals and the like out of the house because she wasn't constantly being urged to crave them.
Oh, yeah, and the noise. Did I mention how much I appreciated the lack of constant noise? My daughter would tell you, I think, that she had a relatively calm and focused childhood without all that distraction. We were happy. She liked it so well she wants the same for her son.