I think by Commercial they mean Formula. But what the heck, eh? I don't see any reason why people can't make money from their art. If they can't, there'll sure enough be a dearth of artists after a while won't there - after they've all starved to death.
If you're artist that is doing your own music and then decides to do your own music AND some music you can sell and earn a living, there are two different terms to name that decision. One group of folks will name it "selling out." Another group of folks will name it "smart." They're both right.
- Zurf