While I appreciate the sentiment of this post, I don't agree that it's was ever intended to be an "idyllic view" of the past.
- Fantasyland is a collection of fairytales and stories with a variety of themes. There is nothing past or present about it. They are a collection of fantasy settings. This land has no cohesive setting or theme and will never really go out of style.
- Adventureland is based on a mid 20th century sense of adventure with jungle exploration and pirates. It only appears to be looking back because this idea of adventure is nearly a century old. Today's sense of adventure is mostly with space, science and technology. If you were going to build Adventureland today without any bias to the existing parks it would look COMPLETELY different. So your idyllic view of this land is pure nostalgia.
- Tomorrowland is based on, again, mid-20th century view of what the future would be that evolved into a cute retro vibe over time as that style of pop culture faded. Again, if Disney were to remake Tomorrowland without bias to what came before it, it would look completely different.
- Frontierland is a setting for cowboys and indians. Again, another mid-20th century pop culture setting that slowly grew out of favor with the cultural zeitgeist. At this point the TVs and Movies of the past are long out of favor and the majority of people visiting are no longer those that have fond memories of westerns they watched as kids. If Frontierland were to be remade without bias it would probably closely resemble what we're getting. Vistas of nature's bounty, forests and mountains. It's a shame the river has to go, but I hope we still get water in some fashion.
- Frankly if Disney were to remake a land it wouldn't be a Frontierland it would probably be some other theme.
So the psychology here is that a combination of your own nostalgia for the parks, your own desire for things to remain the same. Fear of change perhaps. The other is that the parks have remained generally the same for 50+ years at this point that they in themselves have become sacrosanct and in becoming sacrosanct they have become more than their original intention and design to you.
