He didn't need to do it, and it taints anything he touched after '99. He was a legit 40/40 threat every year, and maybe even could could have been a 50/50 threat. He was always a jerk and I hated him long before he was a Giant. But he was probably a HOF'er without the roids.
The idea that roids didn't impact his game that much because pitchers were doing it is a silly argument. The only real benefit pitchers got out of it was the mitigation of the possibility of serious injury. They still had to be able to pitch. Like with Clements...he was a dominant pitcher whose career was only lengthened by roids. As much as I hate that guy too, he was one of the most dominant pitchers ever, and steroids just kept him in the league longer, making his lifetime stats hard to take seriously. On the other hand, Bonds' arms, head, and thighs all made him look like a different person. It absolutely gave him additional power and an advantage game to game. To say otherwise is just delusion.