Was Anthony Bennett a reach? If he's a good player, we'll never know. We do not know if somebody else would've taken him at 2 or 3. I believe though that it is fair to say that the front-runners for that top pick, Noel, Len and McLemore, would have been reaches. The draft process proved it when they went 5, 6 and 7.
We had been told for months that Nerlens Noel was the best player in this draft. Five teams passed on him. Pretty sure after that we can say he was not viewed as the best player by NBA talent evaluators. Same can be said for McLemore. Six teams passed on him. The Cavs could've actually done that garbage trade with Phoenix (the rumored picks 5 and 30 for 1) and still come away with Noel or McLemore. That being the case, you'd have to say those guys would have been reaches at 1.