"A horse is a horse, of course, of course"

Truth be known, I know less about horses than I do about art, I was just trying to use your own example. Let's try again.

It seems to me that the goal of an artist, whatever medium he uses, is to make you feel something. Maybe that's why textbooks aren't as interesting to most people as novels. The textbook just gives you information, while the novel engages you so that you feel like you're part of the story. There's information to be found in most novels too, but some of it isn't true, and you have to figure out what part is true and what part is just artistic license. With the textbook, it's all allegedly true, but maybe the pure truth isn't as much fun because there's no emotion associated with it. A text book about horses might tell you what you need to know about horses, but it wouldn't give you the feeling that you get actually riding a horse which, in my case, would be frustration. A painting or a song about horses might give you some of that feeling without leaving you with a sore ass afterwards. This is probably why most people would rather see a science fiction movie about space travel than to actually travel in space themselves.

Some song lyrics are narrative, they tell a story, while others paint a picture or just create a mood. Like the visual arts, they may be realistic, impressionistic, surrealistic, or abstract. Instrumental music can't actually tell a story, but it may be based on a story and, if you are familiar with the story, you might "see" it in the music. Then again, you might see a story in the music that the author never intended to put in there, which is okay too. A really good song is one that appeals to a broad audience, and each listener feels that the song was written specifically for him. Dylan was like that in his early years, and maybe he's still like that, but you couldn't prove it by me.

Technically, rock, blues, jazz, and swing are types of folk music, but most people don't think of them that way, rather, they would classify them as "pop". Truth be know, though, the folk music of today is the pop music of yesteryear, and today's pop is tomorrow's folk music. Classical is a little different, probably because it's more elaborate than pop music. Steven Foster wrote for the pop market in his day, but now his music is considered to be folk. Strauss and Mozart also wrote for the pop market, but their stuff is now considered to be classical.

It sounds like you have followed various trends in pop music in your lifetime and, of course, trends come and go. Traditional folk music certainly did not "disappear", it just fell off the top 40 charts for awhile. Give it a century or two and it will likely come into fashion again, and the younger generation of the day will think that they invented it. I have not followed the pop trends that much. In fact, the neo folk revival had been going on for years before I became aware of it, not because I wasn't a folk fan, but because I wasn't a pop fan. When I was driving school busses, a kindergartener once asked me what kind of music I liked, and I told him "classical". He then asked me, "What's classical?", and I told him that it was really old music that had stood the test of time because it was so good. He said, "Oh, you mean like the Grateful Dead?" I told him that I had heard of the Grateful Dead, but was not familiar with their music, so maybe he was right.