GreenTengu
Adventurer
OK, per the Reddit AMA Table of Contents, which was clarified by the OP, there are only 13 races: seven that get full write-ups, and six that get just crunch in Chapter Two, and refer to Chapter One for fluff: Goblin, Hob, Bufbear, Orc, Kobold and Yuan-Ti. No other Player stats...
I would wager that has a lot to do with the others not being presented as antagonists in the book. In effect, the 6 that "don't get fluff" probably actually get considerably more in the book than those that get the two page write up and aren't really mentioned or described elsewhere in the book.