SJS, books are not all educational, but generally reading as an activity is perceived to be more intellectually engaging than playing with electronic gadgets or watching television/ movies.
Reading can be a solitary & even isolating activity. My kids do read a lot, but besides reading to my younger kids (& my older ones if they’ll let) I also talk to them about what they’ve read.
I agree with Dr. Pepper that depriving children of something can make them desire it more. When I was growing up, my parents had a television, but my siblings & I didn’t spend much time watching it (probably because my parents didn’t spend much time watching either). Most of my high school classmates did not have televisions at home. Many of them still watched more television than I did–at the homes of friends, grandparents, and babysitting clients–and spent much more time talking/ thinking about it.
edited to add:
That said, I don’t have a television at home now. My children do play computer games but I try to limit this somewhat. Most of them are very active, & none are at risk for obesity.