CosmicSage

I see what you mean. This will be further explained as the story follows and more chapters are released. It was never mentioned they weren’t powerful race but you must remember Saiyan aren’t human and don’t have the near infinite ability to breed as we do. It also becomes harder to birth children the higher your cultivation reaches. Not to mention Saiyans are a warrior race so they are battle prone. Adding all these and some more hidden factors, it makes sense that they would be a small race in this large universe, like mysterious ancient race.

What led you to that thought ?

He will discover more about his ancestry as the story unfolds