If you enjoyed, or at least "got" something out of the Lynch, you might also the film documentary 'Jodorowsky's Dune'. Is a man with a fantastic vision he is unable to instantiate, an artist? Asking for a friend.
By the way, "The War of Art", and its sequel, "Turning Pro" are fantastic books on this topic. These books would be my number one recommendation to anyohe who aspires to be an artist.
I haven't seen the film but this is the defining part of the "artist" title for me. It's not that he wasn't able to instantiate his vision, but he made an attempt and that attempt had an impact on others. That is the art, and it's all performance. The instantiation doesn't matter so much as a message with receivers. If the receivers of whatever happened with his Dune weren't there, then I guess I would still call it something like a "lost" art. Still art, but unrecognized as such. And I'm not sure that would have mattered to the artist anyway.
I highly recommend checking out his work.