I also point to the experience with different media as well. Movies and theme parks are different, but having movie backgrounds gave the original Imagineers the experience to naturally build a scene, and populate it in a way that really spoke to consumers. I've long though Emile Kuri was an underrated contributor to the success of Disneyland. Theme parks haven't really seen that sort of thing again until Stuart Craig and Alan Gilmore's contributions to the WWoHP. Innate skills that people who only design themed entertainment may not have honed.In a lot of ways it’s a problem of being too inspired and too passionate. Being a theme park designer is now something to which people aspire. You can get a degree from known universities in themed entertainment design. So the inspiration in theme parks, and especially Disney’s parks, is no longer the real world but theme parks themselves.
Go look at Joe Rhode’s Instagram account and it’s about people, places, art and history. His fascination is with the real and he imitates that in his work. Herb Ryman was known for his traveling to paint. As was Marc Davis. Hench vigorously studied philosophy and design theory. When Walt brought in Nelbert Chouinard to teach the animators she didn’t have them copying animation but real life subject. When it came time to make Bambi they brought in real deer to study (Andreas Deja recently posted on his blog reactions to The Lion King from some of the old guard and Marc Davis complained the lions looked to cartoony). The lands of the parks were built very much as real places, or at least the illusion of real places whereas now they’re built as fake places. New Fantasyland 1983 drew more inspiration from European villages than the films that inspire so much of the land’s content but Nee Fantasyland 2012 is very much drawn from the movies first and foremost. The parks have moved from copies to copies of copies.
This has also combined with increasing specialization. The visual elements of theme have become something distinct, an application applied on top of a box. Disciplines have become more layered instead of melded together and intertwined.
We talk about the financial / creative pairings at the CEO level leads to success, and not so much about how a pairing between a movie production + theme park operations could be likewise beneficial. I don't know how much of a door goes between studio ops to WDI, but I would like to see what would happen if there were more of that again. But the good studio people might prefer to slide between studio projects or different productions studios, and don't consider themed entertainment as something they want to do or is a step back.