I lay a lot of the blame on Disney's marketing over the last 5-10 years. Same as they did in some part of the '70s, they relied way too much on characters and childhood things for their image in marketing.
Walt used to broadcast from the park, as a backdrop to all kinds of stories; but also showed Louis Armstrong and others performing at Disneyland in more grown-up events. And of course he used to have programs that showcased science, talent, and imagination. Those things we saw translated to the parks as attention to detail.
Likewise, for a while in the late '80s and in the '90s, television programs on The Disney Channel (such as WDW Inside/Out) showed the world all kinds of interesting things, from topiaries to amazing food to EPCOT world showcase. They even had a "National Teachers Awards" sponsored by Disney for a while, which showcase amazing teachers.
And food networks and the travel channel showcased Disney on an adult level, too. They still do sometimes, but cannot do it alone.
The bottom line is that Disney has stopped showcasing anything other than pixie dust and characters to the public.
When was the last time you saw anything other than a castle representing WDW advertising? Why would anyone who has never been there think that it is anything else?
Not to mention a place with whitesand beaches, speedboats, interactive zoological experiences, international cuisine, world class golf and hotels with themed pools, lounges, dinner theater, luaus...