Evidently nobody was sitting close to the door plug. Had there been someone there and they were unbuckled, there’s an excellent chance they would have exited the aircraft. It also happened at 16,000’ so the differential between cabin altitude and actual altitude wouldn’t have been as great as at cruising altitude. At higher altitudes the event would have been much more violent, and by that I mean people would have been bleeding from places they wouldn’t think they could bleed from. It would have also caused internal injuries for many and likely death for some. At cruising altitude the span of useful consciousness is measured in seconds. If the flight crew doesn’t get their masks on in time, they fall asleep. I don’t know if the 737 has an emergency descent mode. Some aircraft do and the plane will automatically descend to a lower altitude where the crew would have some hope of waking up before running out of fuel. As a pilot of such aircraft you train for such situations, but it’s every pilot’s worst nightmare. The masks in the cockpit are designed to be donned in seconds, but there’s going to be a lot of very chaotic things going on and there’s just no way to train for that.
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