Well the market leader is WotC, who seemingly have a suitable marketing budget to promote about three "big dumb campaign" type books a year, which then quickly get read and reviewed by influencer types who haven't actually tried to run them, make most their sales before many people have actually gotten far into them, and are probably profitable more as a driver of interest in the core books and other goods and services then as products in and of themselves.
Also module presentation is based on what the people creating it themselves have read and are used to. Tradition runs strong.
And of course even if the presentation of a module to the gamemaster is needlessly bizarre, belabored, and byzantine, the end user experience for the players can be awesome, which often leaves the gamemaster also feeling good about the experience of the module which so carelessly abused their time and attention.
But I personally have never really experienced modules that weren't a pain to run. The idea intrigues me...