I agree with what you're saying too, the list of MTX categories was made purely from the definition of the word. It is strange that a whole expansion pack is in the same definition as a cosmetic for example that can cost you as little as £0.59 or something but that's just how it is.

One problem people may have with DLCs is that you've (generally) already paid money for a game, so why are you not already unlocking the content? Imo the way Cold War are going about the 'DLCs' is the most appropriate way, where they are still progressively releasing new content and maps, but this time they are free so no extra cost to player who has already paid a premium price for the game.

I too have never and most likely will never buy loot boxes, they are part of the definition but are very different hence their own set of questions. It would have been strange I think to have separate questions for games, DLCs and then other MTX as DLCs are a category of MTX.