I wonder if it would be possible to switch to a Paizo-like model, where the main source of revenue is subscriptions to adventure paths and lore content, with the mechanical rules being added to the SRD on a delayed schedule.
D&D has an abundance of settings to draw upon, and they've namedropped a bunch already.
But being able to throw money toward a specific campaign setting and get tailored content? Might be nice.
Maybe an inexpensive monthly subscription that gets you bits of content at a steady pace, that is eventually compiled into a PDF and released as a normal print book for non-subscribers.
Like, you could spend $3/Month for Eberron, or Forgotten Realms, or Planescape...
Or you could pay a higher price ($10?) for an All Access Pass. But assuming that they release a certain percentage of a book each month, eventually it would be equal to (or slightly cheaper) than buying a book each time. If you don't actually get a PDF it could be cheaper? Spotify for splats?
Maybe they could work in something like Fantasy Ground's new Ultimate Subscription, where you can share books with a small group of friends.