You do realize, exposing the "inner workings of the game" seems to be at least somewhat responsible for massively increasing the appeal of the game in other cases? see Minecraft, Rimworld, KSP as a few examples...
I mean, I agree that games should be moddable, but not from the premise of game profitability and popularity.
The highest-grossing video game franchise list is over-ran by products that are , pretty much, famously unmoddable.[0]
[0]: https://en.wikipedia.org/wiki/List_of_highest-grossing_video...