>>530431465
Vegeta in DBS does say a civil war was bad enough it caused the saiyans to move to another planet, and more importantly, the SSG legend talks about a few good hearted saiyans questioning the evil acts of other saiyans, possibly most of the species, and this is all probably before Cold made them part of his empire.

As far as intent goes, it does seem that saiyans were always supposed to be evil with Goku being the exception, and that's specially noticeable since Freeza originally didn't exist (Since Raditz and Vegeta both talk like saiyans are self employed initially). So I'd say that if Cold/Freeza made them worse, it's not that much.