Arguably, framing someone's life behavior as functions of usefulness is antithetical to the need to engage in recreation. The following of TV is useful if your social sphere is amongst other people who watch TV. It builds a canon in which to socialize, discuss, invite people for watching parties, etc.

(I myself do not watch tv but I also have no desire to presume anything of people who do. I at least personally acutely feel a loss of culture because TV and movie watching is very common in socialization rituals and I am unable to engage in them.)

There are better ways to socialize and watching television should be the last one. Talking with other people about movies and television shows is superficial and won’t help in bonding with them, because your personality lacks depth.

People have said this about every media since the book was invented.

Is it wrong, though? If you spend all day doing nothing but reading books, you're not using the time to apply anything that you have read in a book

That's how I feel about programming books.

Did someone measure it and proved them wrong?

I am not saying you are wrong, or he is, but the ancientness of the claim is not an argument in favor or against it

Both function much like a drug: pleasant in small quantities, but easily creating a feedback loop that results in it dominating your behavior. Some people appear to be more susceptible to it than others.

The neural mechanisms have a lot in common. Video games, I would note, also share that mechanism.