Artists/Musicians/Film Makers etc. shouldn't have to cater to what the fans want.
Definitely, but like Calvin pointed out above, I think there's a line between catering to the fans and getting some second opinions. Just take the scripts of the prequels for example. They feel like first drafts that Lucas didn't bother to get a second opinion on, he just finished a rough first draft and then went with it. He could have told the exact same story, but tightened it up and gotten some help to write dialogue. What Lucas really struggles with in the prequels is writing characters and specifically writing how they feel, without them saying how they feel. Think about it for a second, most of the times the characters talk about how they feel, instead of conveying it through acting or other means. Darth Vader's "Nooo" is a great example of this. Lucas couldn't come up with a good way for Darth Vader to be upset over Padme, so instead he wrote this comical line which resulted in laughter in theaters. The Anakin/Padme lovestory overall is a good example of what Lucas does poorly. Instead of showing us why they are in love, the characters just keeps telling us they are. Same with Anakin and Obi-Wan really. We are told about their adventures and great friendship, but all we get to see is Anakin whining about how Obi-Wan is annoying, never trusts him, and so on. Obi-Wan also shows annoyance with Anakin, yet in Ep IV he talks about Anakin and says "He was a great friend", something they failed to show us.
That's ultimately one of the mistakes of the prequels for me. We are being told about characters reactions and feelings for each other, instead of experiencing it. In the old movies, we got to see Han/Luke become great friends through shared experiences, and there was a more natural evolution to relationships. The Leia/Han lovestory was great and also evolved naturally, and just compare that to the forced Anakin/Padme lovestory with "That must be because I'm so in love" -"No.. no.. I'M so in love with YOU".