You just said it yourself, you are assuming people photoshopped it. And to assume it's shopped is to also assume it was leaked through a legit name, company, LinkedIn profile, movie produces, actual autocad code, and more.
You see how it being fake makes it that much more complicated? I'm not making this up
Let's say the image is real. This means someone -- or a group -- had to design it, get the greenlit from whatever company they work with (in this case Nintendo, etc), have it sent to an advertisement manufacturer (which requires autocad and all of that), then the new ads are most likely put in Nintendo's possession so they distribute it (most likely for kiosks for stores, conferences, etc), which requires putting on trucks and that requires a director of some sort, and so on.
The process to bring something real to life is arguably more complicated or at least just as complicated as faking the image (which requires the process you mentioned). That is just one of like a billion ways you can look at it.
I believe the leak is real, I didn't even want to talk about Occam's Razor in the first place (this got started by me asking if we could not talk about it), and I'm sure you are right yourself in another 1 of the billion ways you can look at it.
My point is bringing up Occam's Razor in a Smash leak discussion when a simple outcome hasn't been found -- because I really don't think it has since we have hundreds of pages of arguments making both sides look like either a simple or complicated process -- is an extremely weak argument that just promotes less discussion on a site (or more specifically a thread) that is promoting discussion. It is also being used as just a quick "I'm right" card to be played. Honestly, I'm just going to leave it at that.