I don't get where you are getting "players want all this options" thing from.
I'm talking about my friend whose entire pitch was "It's like the Roman empire"and until the player peppered him with questions did they understand what they might be signing up to.
Because what should come as a surprise to no one, every DM doesn't have a wiki, worldbuiding site-link, or printed physical primers for all their settings. But as worldbuilder/storywriting sites grow and a possible DM matching site develops, the number of DMs who have openly displayed settings will grow.
The contract will always favor the DMs but the bar for quality DMs will raise due to exposure. It will be easier for players to turn down DMs as they wont be trapped with the few DMs of their town.