I'm not seeing a major difference in your argument. While there's a difference in the exact nature of the transactions (art being a single large sale versus music as lots of small sales), there's not much difference in the way commercial success affects inspiration and the external financial pressures that cause both artists and musicians to make "safe" choices whether consciously or subconsciously.
You could also argue the capital issue given that artists typically use galleries as sources of capital, while musicians/bands use labels to capitalize their expensive projects. Both in art and music now, though, the creators are funding the production in exchange for much larger chunks of the sales. Hirst and Radiohead have a lot in common in that respect.
That's a pretty major digression from the topic at hand, though.
JB
(Art Director for a group of art magazines.
)