I imagine its a point of emphasis against QBs who escape to throw. And the rule of thumb is if you are the deepest you have to stay deep until you know the throw isn't coming toward you. Its possible they all thought he was going to continue forward and either throw or run when he rolled to his right at first. that probably broke typical coverage on that play. Pass rush always helps. Not even Rodgers sees all WR who break free while improvising.