Change of Music?

Recently, I decided to re-listen to pop artist that came out early 2000, and even years before them. Now, I have a question...what happened to pop songs that actually based around real meanings?

Don't get me wrong, there are pop artist out there that still do that, but they are not as recognizable it seems. Everything seems to be revolving around appearances than anything. There's glitter, short skirts, tube tops, and close to nudity shots. There's lyrics about pure sex (which isn't that bad for some, I guess.), about hooking up with a guy.

Basically, what happened to music in general? Not even just pop, but other genres as well. Music seems to be changing so much, and it's only been a couple years for this jump to happen.

...Though, I have to admit, I do like some of those pop bands that are out now, but it just makes me wonder how all this happened.