What if Frieza never destroyed the sayains?

Kakarot and Bardock(Kakarot as an adult)

Kakarot had trained every day for twenty years, and it had paid off. He had gained a power level of 12,000 and even defeated his father in combat. He had mastered the Kaio-Ken technique and had even learned to use SSJ4(Super Sayain Four), he had beaten every single sayain known to sayain-kind, or he had thought. He had beaten his father Bardock, Vegeta Jr, and even Kinv Vegeta! After the kids in town heard about how he had beaten all them, they were all too scared to even try to fight him. He had really wanted a challenge, but everyone was too weak, little did he know that very soon, a challenge would come right for him.