Obama was significantly less evil than Biden, who was himself not as competently evil (at the time of his presidency) as Harris is / will be.
Obama picked Biden as his VP in order to shore up the more evil, racist, conservative side of the Democratic party and undecided “moderates.” He was a segregationist, a virulent racist, a sexual abuser, and a lifelong monster.
Obama wasn’t a good guy either but the trend is definitely toward greater evil.