We are not talking fatalities, we are talking casualties. You cannot convince me that an explosive decompression at 16k feet won't cause serious injury at the least.

Edit: seat belts are designed against the forces of severe turbulence, not explosive decompressions. Assuming the seat belt actually holds, all the forces are applied against the single point of contact the belt has with the midsection of the passenger. Reminder that the forces were enough to torque two seats, rip the padding off the closest seat, and ripped the shirt off a nearby passenger. I actually think there is a decent chance there would've been a fatality should anybody have sat in the closest seat.