Remathilis
Legend
I mean, you can make pretty much the same argument for almost every class, as well.
There's certainly a strong argument that greater mechanical specificity, and more heterogenous design, strengthens the narrative presentation of the concept. (Not an overwhelming argument, but strong.) But greater specificity is also going to have a trade-off with less versatility.
Having a race with 3 choice points, each of which has 3 options, is simply easier to fit into a book than 27 different races.
I can and I did!
Though the thing is homogeneous design ends up reducing their impact on the world as well. For example, the aarakorca, harengon, tabaxi and tortle are all unique separate species with distinct designs (both mechanical and aesthetic) and lore. Combining them removes those unique elements, makes them all one people, and forces them all into one style and story. Remember the ardling? How the second attempt tried to make a generic animal-headed species and it failed to capture the essence of any of the animals it was trying to emulate? That's what I dislike. And I would gladly take 27 dedicated options over a dozen sourcebooks to one mediocre option in the PHB.