Not necessarily true; you're talking about 2-Man, and this looks like a straight Cover 2. The underneath defenders all bump their first reads, but then pass them off to other zones; the CB at the top bumps and has flat responsibility (watch as he hands the WR off to cover the RB coming out of the backfield). That might be West's initial mistake; he seems to be misaligned at the beginning of the play and is too deep to bump his man, giving the WR a free release down the sideline into O'Hanlon's zone.