Uh, no, it's not networks who are holding things back... it's consumers.
Not everyone in the world has internet, let alone computers for various different reasons, whether it's cost (it's not exactly cheap), location (some rural areas can't access internet), or people who don't even know how the internet works (older people who are tech savvy, or little kids who really shouldn't even be using the internet yet).
In fact, internet is holding back themselves: there's a number of shows, movies, specials, what have you, that studios refuse to release on DVD or Bluray, in superior quality, because apparently there's no "market" for them, so people turn to the internet, like YouTube or something, to watch them, in iffy, varying qualtiy, only for them to be removed for "copyright".