Wasn't that the promise of the early cable TV? How long did that last?
No, early cable TV was a way to provide signals from broadcast (and, thus, ad supported) channels to areas where, for geographic reasons, there was poor reception.
(The CATV acronym frequently used for cable TV originated as an acronym for its earlier name, "Community Antenna Television" -- reflecting it as a model of consumers sharing an antenna to receive broadcast signal.)
Premium, ad-free content, cable-specific programming didn't turn up until decades later. So, you've basically got it backward: instead of being something that originally promised subscription fees for no ads content but fell away from that, cable is something that initially offered subscription fees for access to ad-supported broadcast content but later evolved to include subscription-based (and pay-per-view) ad-free content available on top of the basic ad-supported content.
I'm not sure what Netflix's endgame is, but they're leaving a LOT of money on the table by going subscription-only.
Hulu isn't the future of TV; Hulu is the future of TV as envisioned by a bunch of major TV networks. I think HBO and Netflix are closer to the future of TV than Hulu is.