Yes, I worked in the Book Department from 1988 to 1994 and was at one time series editor for both the Ravenloft and Realms fiction lines. I was also the go-to for RPG–fiction crossover projects, which was one reason why I got recruited to the Dark Sun team early on, immediately after Mary Kirchoff, Tim Brown, Troy Denning, and Brom had fleshed out the initial goals and creative vision. I was the editor for the first five Dark Sun novels, the Prism Pentad, and might have continued as primary Dark Sun fiction editor had the Book Department not moved away from designating series editors in late 1992/1993.
Dark Sun as a whole was a deliberate attempt to present game material, fiction, art, and graphic design with a coherent creative vision from the release of the first product. The idea was the fiction and games would be complementary, but not compulsary. To link them too tightly would have severely limited the potential fiction sales, which were assumed (correctly) from the start to have a much higher ceiling than the RPG sales. You could read the fiction without playing the game. You could play the game without reading the fiction. If you did both, the product lines had creative and aesthetic through-lines, but they stood alone just fine. The goal was not to force customers to buy everything.
Mistakes were still made--the Dark Sun novels and the metaplot probably should not have undermined the initial boxed set, for example. Not a shock, as the company and the individuals working on the various lines (even the products within the lines) were still learning how to coordinate these kinds of things. But the goal, at least for the creative teams putting the Dark Sun products together, was not to manipulate the readers and players. The continuity was more a reward for the superfans than a goad for those who were buying only the games or only the fiction.
Metaplot is neither good nor bad inherently. It all depends on how (and why, which shapes the "how") it's implemented.
In larger terms, the success of the fiction lines at TSR, with the novels selling to many more people than were buying the world-focused game material, meant the company had an interest in aligning the game products with the fiction. If someone read a Ravenloft novel and wanted to try out the RPG, it made sense to have the game material welcome them with the same Strahd they read about in Vampire of the Mists or to provide Realms players with the stats for the characters from the fiction so they could meet (or fight) Elminster or Drizzt, which explains Realms supplements such as Hall of Heroes. This wasn't always easy to pull off, and there were many missteps, but that was the idea. It's a way to use the success of the fiction to potentially grow the audience for the game and make the game more friendly for the newly RPG curious poking their heads into the game store for the first time after reading the novels.
A significant number of fans for any IP want tight continuity, and this was a growing and common sentiment in the 1980s and 1990s, especially in the US TTRPG market. They want all releases across all media to tie together and to be consistent. That's still the case for some fans. You see it throughout the internet in wikis and all kinds of other manifestations of continuity-themed lore bibles.
While some fans still want tight continuity, the overall lack of tight IP continuity being implemented by WotC now makes sense in the current market. The RPG as a game concept (you tell your own story around the table, even playing in shared worlds) is more widely understood and media audiences are more sophisticated and accepting of variations between media. It was a different market in 1990. Some design giants, such as Greg Stafford, started in the earliest years of RPGs from the notion that "your Glorantha will vary" for every individual group or player, but he was way ahead of the market as a whole. Not a shock with Greg.