Yes, Steve Wozniak is certainly quite overrated. This is not because he is not an exceptional engineer. However, because of him a lot of other amazing and capable engineers and scientists that helped in building up the industry became eclipsed.
This is the same industry through which Wozniak was able to become the brilliant person that he is in the first place, at the right place and time. However, even though he is overrated, one should not forget the fact that he was extremely capable and indeed one of the best innovators of all time at the Silicon Valley.