Wrong. Yes, the Bills should have taken Ngata, but the pick was not bad because they "reached" the pick was bad because it was a poor choice to take him at all.
I hate the "reach" label because it presumes you operate in a vacuum where: 1) You can trade back to a later spot if you want that player 2) pre-draft rankings are absolute and irrefutable. Ryan Leaf wasn't considered a reach when he was drafted.
The term identifies where a player is projected to be drafted and then evaluates if the player had good value for where they were taken. The fundamental flaw with the system is that players are rarely drafted at the spot they are projected to go in. Other posts have addressed this issue. The best of the best prognosticators are wrong 75% of the picks they make.
The only time I would think of using the term reach is if the player would have definitely been available with the team's next pick.