Vegeta is the name many characters in the story Ultimate Kakarot since all rulers of planet Vegeta were named Vegeta. There have been Hundreds of Vegeta’s in the Saiyan race. The original Vegeta was a pure Saiyan while future Vegeta’s were Saiyan hybrids even though none of them were part human because all the humans were killed. Vegeta settled in the next planet Vegeta. Vegeta became a Super Saiyan after Kakarot.
He doesn't care about the other Saiyans since the death of Raditz and Nappa meant nothing to him.