Anthony Bennett is the worst #1 overall pick of all time, not close. He legitimately can't play. Olowokandi and Brown were both serviceable backup big men, who wouldn't have gone down as busts if they'd been drafted at #20 instead of #1. Bennett is a bust at any draft pick, he's not good enough to play in the league and went #1 overall.
This draft still probably isn't as bad as the '00 draft, though. Steven Adams is another guy from the draft class that is going to have a solid career.