I believe channels are here to stay for the same reason weekly sport is here to stay. Why weekly sport is here to stay I don't know, but channels provide it live for a price now and they're going to keep that market by hook or by crook. Seeing other stuff when first shown doesn't matter quite so much, but it's very important with sport.

We've also the example of radio, which despite being free has done fine over the years despite an increasing range of alternative entertainment. I don't see why broadcast TV can't survive too.