What is art?
for me art is the intentional expression of creativity using skill within one or more media. Admittedly many remove skill or intention. Certainly something that doesnt employ skill, creativity or intention can be perceived artistically.
The point is that commercial pieces can be just as artistic as uncommercial pieces. The distinction is in fact between art produced for yourself, versus art produced for a specifc audience or audience other than yourself.
Of course you can produce art, including music, for both yourself and others... so it isn't necessarily black and white.
What I often see being misunderstood is the wooly notion of "artistic integrity". The notion that somehow by producing commercial music it is either unartistic or that everyone who makes commercial music is unartistic, or has automaticallly lost their artistic integrity is something put forth by people jealous of the commercialsuccess of someone else's music, even as fans this can be felt. To me artistic integrity is compromised (if anything) when art is modified for commercial reasons only. Does thatmake the work artistically invalid? nope... or we would have no music industry!
Is it wrong to make money from art? Not at all. Is it wrong to write something that has a popular appeal? no way.
A writer can be self indulgent or not, but that is not the same as uncommercial versus commercial, artistic vs unartistic.
It is something levelled at musicians... as if artists dont need to eat or pay bills. Next time a builder repairs by house and doesnt expect payment because he did it for the pure expression of his craft I must ask...