This is a question that I'm struggling with.
Clearly my mother's way was effective (I didn't watch much TV as a kid, and stopped having a TV by choice in my early 20's), but it wasn't very nice. She would just constantly tell me that various shows were for "stupid people". I'd start watching something, and she'd say, "K, that show is for stupid people! You're not stupid! Why would you want to watch a stupid people show?" Very few shows fell into the non-"stupid people" category.
Now, to some degree, I do agree with her about most TV shows being really stupid. But I don't think that's how I want to approach it with my son when he gets old enough to notice TV. We won't have a TV in the house, but I want to have ways of explaining and normalizing why that is, and why we don't feel that TV is a good use of time, without shaming him or putting down people who do choose to watch television. I also want him to learn how to self regulate TV watching when he's at friends' houses, and how to (positively and politely) suggest that he and his friend do something else when he's bored of the TV.
Any suggestions? What do you all do?