True, but as usual, that’s offset elsewhere in the grammar (and a binary or ternary noun class grouping doesn’t really introduce that much complexity into the system).

English still has number distinctions with multiple irregular patterns (and plural/collective distinctions like “fish/fish/fishes”), and even lesser recognized animacy distinctions that must take up some space in the grammar too (“my face” is fine, but “the face of mine” is odd, while “the clock’s face” and “the face of the clock” are both fine).