Their preferred customers are people who will spend money on their products.
The problem, right now, is that they aren't sure which products will get enough people (whatever that is) to spend money. That's why they're so firm that D&D "isn't [just?] a TTRPG, anymore". They think that video games and maybe books will bring in more money (have a wider audience). I'm sure the gold ring is to pull a Marvel and have D&D spread across movie/TV screens to the point where the RPG is a footnote.
Where I think they're looking at it wrong isn't in trying to expand into other markets. It's that D&D can't and won't translate well to TV/movie. D&D doesn't have a story. D&D doesn't even have a real setting. Forgotten Realms has a story and setting. Eberron has a story and setting. Dark Sun has a story and a setting. Those are all things that could be put into action. If WotC can figure out that they don't just have one "brand", but have several, they might actually be able to pull it off. Right now, they don't seem to have a clue.
Yeah, you raise a good point--D&D, by its nature, cannot have a single narrative or story, because it's (theoretically, anyway) supposed to be an engine that
powers a story, whatever story the DM wants to tell. Whether that story is
The Epic Of <Our PCs>, or
How To Killinate Everything: from Aboleths to Zombies, or
It's Their World, You Just Play In It, the game acts as some kind of platform or engine for each individual group's desired *thing.*
Dark Sun, I feel, would be an excellent choice for a movie franchise. It's a dystopian world, ripe for change, perfect for gruff anti-heroes and classic Conan-esque "sword & sandal" storytelling. Heck, you could probably do worse than just adapting the "Prism Pentad" (or whatever it's called) to the silver screen. And if those sell well, branch out further: there's still a market for "monster of the night" films as illustrated by the
Underworld series, so Ravenloft could work; a freewheeling, pulpy action-magic-adventure flick in Eberron could be plenty fun; and Dragonlance has scads of stories that could be told, even playing with ideas like having Raistlin as a villain protagonist or something.
5e may have tried to go back to its roots, but it seems like the people managing the whole shebang have forgotten that D&D, the game, has
always been a means to some other end, and not an end in itself.