Yeah, this is a good topic.
I agree that it's because of the Internet. Why, with the Internet, there's absolutely no need for really anything else electronic anymore, as far as media goes. And considering music is pretty much the easiest to view/acquire (compared to movies or videos games, or whatever else), it only makes sense that people prefer to watch and listen online, rather than "wasting" money on buying CDs, tuning in to the radio, or watching those outdated music programmes. :\
I mean, I honestly don't have a single station working on my TV. I haven't watched more than a few seconds of any programme on a TV in well over a year. And I know many people who are in the same position, even if they have the most advanced cable you can get.
Not only is it so very easy to watch or listen online, but you can bring up nearly anything you can think of in a matter of seconds, and watch or listen as many times as you please. So why bother with anything else...?