In the US, commercial interests stole the airwaves early on, before public broadcasters could get a stab at it. And the deal that was made with public broadcasting was, "Okay, we'll allow there to be a handful of public stations to do the educational programming that commercial broadcasters don't want to do, but the deal is they can't do anything that can generate an audience, anything that's commercially viable." Anything they do that could be commercially viable could be considered unfair competition to commercial interests and should only be on the commercial stations.