Two reasons, one the original game dev or rather company will have to approve whether modders can charge content for their game. So it’s a bit murky on how the business end of it will be handled, and if any legal stuff takes place. Which bring to reason two, the cut of the pie modders get, which the number being…
Simply put, they can’t. The original creator will have to pursue legal action which itself is costly and/or time consuming, and that’s assuming they can prove they are the original creator. Which also begs the question, what if someone create or copy a mod in almost every way but name? Will Valve and the developers…