You can’t charge extra for access though.
This isn’t entirely true. Wheelchairs and ECVs are for rent. The accommodation is the resort being fully accessible with very few exceptions and those fall into the realm of reasonable.
Nobody has successfully litigated that WDW needs to provide mobility devices for all even though visiting the parks might be impossible without them for some people.
Deposits can be required to use or reserve certain tools that are available, like braille maps and audio devices, or need an extra step like reserving Hoop Dee 14 days prior for live ASL interpreter or planning around certain weekdays when live ASL is offered for in-park shows. I don’t think the ADA’s intention is to have businesses provide 100% of what someone needs, rather it looks to ensure reasonable paths to possible.
Not all the beaches around me have wheelchair access, some do. The idea is a wheelchair bound person has options to visit the ocean, where before it was next to impossible. I think most people find it reasonable that it’s not necessarily an inherent human right to visit the beach of our choice; it’s an inherent human right we can experience a beach.
How far is it reasonable to make every public/private beach cover all the details of every issue, and that’s kind of what’s being asked of WDW in some cases. People visiting with babies, pregnancy, elderly regularly adjust touring to their individual needs. Guests arrive with all sorts of encumbrances. I don’t think it’s clear where the expectations on old DAS stopped. It was constantly argued as having zero harm, meant to help issues big and small*, and no limit intended once granted. Does a line exist where too much is too much, within reason?
*small being things unique mostly to WDW that did have other options to manage without DAS, eg mild-moderate sun sensitivity where season, park hours and shielding could compensate well enough to match the self remedy extent dozens of other challenges non-DAS users frequently face