I can't think of any effective solution to this problem besides lowering rack rates.
IMHO, the only solution is a comprehensive rethink of the business and how it's marketed.
The resort today is operating with dramatically increased competition and in an entirely different marketing landscaped than either as first envisioned or throughout the Eisner growth era. There is no way to adequately educate consumers on 30+ resort hotels when you also have to showcase 4 theme parks, 2 water parks, and a lifestyle district.
I'd first recommend reorganizing the existing hotel portfolio into 4 categories, adding a "Signature" or "Legacy" option above the current deluxe (for the monorail loop resorts, and perhaps one or two others if they're willing to invest in). This would add clarity to what each category means, and eliminate the confusion when one standard "Deluxe Resort" room can cost nearly 3 times that of a standard room in another deluxe. Splitting into four categories creates a more marketable portfolio of comparable resort options. This would also allow a more organized planning view for what the minimum standard is for each category: AKL should at minimum have a Peoplemover or Skyliner line to the park, perhaps one that lands you on-show. OKW and SS might end up as the top of the Moderate category based on amenities, and that's okay.
With that complete, you'd need to make your resort portfolio searchable by Resort Category, Resort Area, or specific highlight features (pool with slide, walkable to parks, alternate transportation to parks, etc). This would make comparing options far easier for the consumer.
With things reorganized, you then focus on returning value to onsite stays. Increase early entry to a flat one hour daily instead of the split gate at 60, attractions and 30 as currently operating. I'm not sure if data supports a full return of Magical Express, but at least offer inclusive Mears Connect transportation as part of resort package. Give real priority to onsite resort guests in access to Genie+, however that looks after the system changes are made. Including Genie+ with Deluxe and Signature resort bookings would help directly counter Universal. Focus on returning "magical" extras for onsite guests, like awarding one family per resort daily with a golden Lightning Lane pass... things that make the stay special without really costing anything.
If they could clean up the structure and return some of the onsite benefits, they wouldn't have to cut rack rates too awful much. Good sales structures extract maximum currency from their targets, but great sales structures make the customer feel good handing in their money. The mouse used to be great at that.
Once you can redefine the "value" of staying onsite to equate benefits, not cost, you'll rebuild that base. Once occupancy returns to expectations of 95-97%, you've created the demand and scarcity to protect your pricing model.