Huh? The point is that game developers would never be able to use commercial libraries again. Thus making all development significantly more expensive.
But what commercial software licenses are you using to write backend server architecture for a video game? There's no need for a dependency on FMOD or anything (unless you're doing something very unusual)
They are not able to share that code now because licensing the code in a way that it cannot be shared is currently a viable business model for Unreal and Unity - that would change with the proposed law and the middle ware providers will be forced to adopt different terms if they want to continue existing.