Maybe there are more people in the world who need to feel things, and music can be felt (e.g the sound of the bass) when a picture cannot be felt in your guts? Maybe music brings us back to the days of the when we were all dancing around the fireplace and just blended into the music and to the general mystic atmosphere?
My earliest experience falling in love with music actually had much to do with imagery.. Being taken to a symphony, hearing Beethoven, closing my eyes, and picturing (what I thought at the time) myself riding in a carriage through 19th century streets, buildings going by... But I also felt it as well, and it brought tears to my eyes. Or the first time I heard Hendrix, it was on the Woodstock video, and I was just saw his back.. he looked crazy and awesome.. afro, tassles, etc.. I think it was kind of one of my earliest exposures to someone who really stood out. I didn't even think of his music much until later, at around 13, when I started playing myself. I met an older kid who had a "real electric guitar" and everything, and played Hey Joe.. and I was like "Whoa!! Normal people can do this too?" So I took it up myself.
Is it that musicians are seen as more extraverted and in-touch with their fans and life?
Is public visibility and performance of musicians a factor?
Is visual art perceived as more esoteric and removed from day to day life?
Is music more of an emotional medium, and thus more appealing?
Does the price and availability of visual art play a role? If so, what if visual art were made more affordable and more easily obtainable? It seems to me that one reason the photographer Ansel Adams was so popular is that he tried to make his work available to a wider range of people by selling it for less than many photographers of his caliber would have.
I think a lot of these are valid possibilities. I think accessibility is a factor - not just financially, but even how people relate to the art form. Visual arts now have a very elitist quality to them - they are often expressing some deep feeling, some profound commentary, and they ask you to, well, think. Pop music is accessible money-wise and mentally/emotionally to a wide variety of people, from wealthy to working class. The exclusivity of the visual art scenes, well, exclude many "average" people. It is removed from everyday life in that sense, and it can even come off as critical of everyday life. Actually, I think art has always been that way. I doubt peasants of the past were having their portraits painted...but there was also no recordings of music. The average person was probably a bigger fan of folk music than paintings though. (I think poetry used to be more popular because it has a musical quality, could be carried in small books (god I love those), was accessible to anyone who could read, and often covered rather universal topics.)
Which brings us to the matter of reproduction. Music can be produced & distributed in large quantities and everyone is getting the original in a sense. With visual art, the exception being photography, a reproduction means a picture of the art, which shows you one perspective of it. IDK about anyone else, but a Monet looks way better in person than on a calendar . You see the texture of the brush strokes, the way it changes from different angles, etc.
That brings us back to accessibility, in the form of convenience. Music has become increasingly convenient to get a hold of, to store, to carry with you. It's easy to integrate it into your life and that increases its value to many. Most people will have a greater appreciation for something they have a practical use for, and music can be practical in a way. It provides ambiance through background noise, it's a form of entertainment, and it can be interactive (ie. dancing, karaoke).
I think music is also more popular for the reason is does NOT have to fully absorb your attention. It certainly can, but I definitely feel visual art can do the same (unfortunately, we're often restricted to looking at it in public places where a sense of intimacy is lost - it takes on a tourist attraction quality at times, which lessens the visceral response). Music can be played in the background and not interfere a lot. You can play in your car, at work, etc. You can enjoy it on many levels, in many settings.
As for visibility and performance, I think this is has to do with how music is marketed. Visual art is not marketed as entertainment, so the artists do not become pop stars, and yes, that means people don't connect to them as individuals the way they do musicians. In some ways, I think artists like it that way & musicians envy it - their art can stand alone.
"Charlotte sometimes dreams a wall around herself. But it's always with love - So much love it looks like everything else. Charlotte Sometimes - So far away, glass sealed and pretty." - The Cure
in my opinion music is a lot more popular than visual art because it evokes a lot more when you encounter it. usually art is left up to interpretation of the viewer, unless you are reading a description on the history behind the visual. music on the other hand, expresses the artist's emotion much more loudly as well as allows the listener to interpret in his or her own way.
minor chords will evoke a melancholy feeling like using a cool color palette on a painting. however, music directly communicates with our subconscious...more to those who are open and susceptible to it. visual art takes a lot longer to process in that regard, unless you happen to be an extremely sensory and visual person.