I think you're correct that Bonds' being so unlikable had a lot to do with the rise of PED outrage among baseball fans. People broadly accepted the idea that a talented jerk could make himself into a phenomenal, record-stealing colossus through illicit drug use. Bonds' case cultivated a sense among baseball fans that PEDs made baseball really unfair, and I'm not sure that any analogous example exists in football, for instance. I'm not an avid football fan, though.