It's a science fiction show. If you're into completely taking things seriously, it's probably not the genre for you. Especially the goofy things Star Trek has done to science over the years.
That 0.00002% is pretty close to the odds of everything going right for sentiment life to develop in a given place with the right circumstances anyways. Nevermind the five races of the Xindi on the same planet.
But hey, I'm just an open minded fan. You're the published author, so you stand a better chance of making the TAS bug race into something different if you want.