I'm currently a design reviewer for the ADA office of one of the country's largest transit agencies, and I disagree. I tend to work mostly with infrastructure, and this is more of an operational issue, but from what I've seen it would put Disney is a very risky legal position...and we all know how much Disney's legal team likes avoiding those.
- Modifications to existing facilities cannot make them less accessible. If a building has a ramp leading somewhere, that ramp cannot be removed without providing access to that same area (like a platform lift or elevator). Disney currently provides shuttles from their remote parking facility to the parks; they would have an extraordinarily difficult time removing that, even if the trams for able-bodied guests were also taken out of service. Because the distance is so far (about a half-mile on the tram route, at least 2/3mi through DTD), it's hard to see how this would not be making the parks less accessible.
- Accessible parking spaces must be located in the part of the parking area that is closest to the facility that they serve. At a grocery store, that means near the front entrance; at the existing parking structure, that means near the elevators on each level. However, one could make the argument that the Mickey & Friends parking structure is not the closest parking to the parks; hotel and DTD parking are closer, as are the bus stops and drop-off lot on the east side. This is a murky argument that would be tough to enforce, but it's a unique circumstance (different from a campus, where there is no one "main" facility served by multiple parking locations) and I think it could be argued convincingly
- That pesky "reasonable accommodation" clause. It's tough to define exactly what must be done to meet it, but I think it's "reasonable" that a location charging $20+ to park more than a half-mile from their facility would need to provide some sort of transportation service to the facility entrance. Relocating wheelchair rentals (or even letting guests borrow them for free to get to the main entrance) would not meet this; forcing people who don't routinely use mobility devices to use them wouldn't pass muster
I also can't see them doing a whole lot to spruce up the existing tram path to make it a pedestrian route. I don't remember the specifics on the Eastern Gateway walkway, but I think it was about 30-50' wide. The existing tram path is about 30' wide with narrow landscaped buffers on either side, hemmed in by Disneyland Drive and backstage facilities. In order to accommodate the massive pedestrian volumes, they would likely need to keep the width the same (or expand it), which doesn't leave much room for a meaningful DTD expansion there. They could add some ODV and other kiosks, but there isn't space for meaningful retail, dining, or convenience facilities in that area. The main route will likely go through DTD, which will need some modifications to meet the increased traffic
I agree that the trams will most likely be removed as part of this project, but I can't see how they could also get rid of the accessible shuttles. And if those shuttles remain, it's likely that people will try to "cheat" the system just like they do with the disabled passes in the parks, leading to poor service for the people who truly need them. I struggle to see Disney building a real transportation system here, but there really aren't many other good options.