Nintendo blames... itsself???

[A Black Falcon]

You aren't making any sense...

Repeating textures... hmm. The two water levels, the two snow levels, and Bob-Omb Battlefield and Tall Tall mountain share lots of textures. And the level construction of the mountain is vastly different. Other than that, I don't think any share much more than basic grass/sky/water textures while using other things as the main focus of the level design or construction.

Like in the first two levels, the first one doesn't have any of those castle textures in it, which are almost all of the ones in level two. And level two has very little of level one's grass and dirt. So how do they repeat so much?

Almost all the other levels are at least that different.

As for SMS... a few are unique, like the one on the cargo crates and grills. Or part of the amusement park one. But most... aren't. Like the beach (both the beach level and the beach part of the amusement park and several other ones), and grassy field, and others... all so similar! Far, far more similar than almost any two levels in SM64...