Chi Chi is the ultimate villain.
Growing up with the trauma of her mother's death and lots of daddy issues. She was rejected by all the men she met (Yamcha, Goku). So she turned into a psychotic feminazi and secretly wished for all men's death.
Think about it. She tried to kill Goku during the Budokai Tenkaichi. When she noticed she has no chance, she used emotional blackmail to marry him. Afterwards she traumatized him, her being the only family for him, so he turned into the emotionally handicapped monkey he is in Super.
Same with Gohan. She noticed his potential so she forbid him to train. One can sense her psychotic nature when she seems unresponsive to the world being in danger and prefers Gohan to study instead. With Goten she was a bit smarter. She didn't appeal to anyone actually strong to train him, instead she "trained" him herself, although she's weak af. So to give him a fake sense of getting stronger.
Chi Chi is secretly contributing to world destruction by active passiveness. Good thing Frieza didn't come across her sooner. Pls support my theory.