I do understand this article; however I would point out that among the "poor" (in America hardly anyone is poor like in the 3rd world) I have met, TV is present and books are not.
I mean, yes, I know what you're getting at, but a $50 used 25-inch CRT that you use for several thousand hours is going to beat out a book on the price front any day. Even just the effort of going to the library and back adds up to more human capital per book/hour than watching TV. I'm not endorsing it, just observing it.
I read thousands of books as a kid and paid for nearly none of them.
TV's information density, even for good shows (however defined), is very low; you can learn far more in 1 hour of reading than in 1 hour of TV watching. And TV is a passive activity while reading a book requires mental involvement.
What people, even poor people, choose to spend their time on has an effect on what they are able to do later.