I dunno why everyone's making a big deal about it.
Just read this:
https://en.wikipedia.org/wiki/Evolutionary_history_of_life
If Earth is 4.5 Billion years old and "life" started as early as 4.2 Billion years ago, there is only 300 million year period with no life at all. Now imagine a planet that while forming was hit by meteors with some microbial life on them. It's in
theory conceivable that life started on that planet at same time as the planet was "born" (formed). If that microbial life evolved much quicker than on Earth (not taking detours for trilobites and dinosaurs and such) then the
Xaheans might very well consider they were born at same time with the planet.
I am all for it. This is what Star Trek is all about. Discovering new civilization and learning how they view their place within the universe.