The descent from FL330 took 210 seconds.
3 and a half minutes. In other words the terminal velocity of most objects due to gravity.
Now, as has been asked many times in this long and sometimes exasperating thread, why? The airframe is said to have remained intact. But, after the initial burst of automated messages, there was no verbal or electronic contact from the aircraft.
We have an object that appears to have fallen from the sky with normal, gravitational terminal velocity. We have no contact from anyone or anything inside it. There was no attempt (it appears) to prepare for a crash landing in the ocean.
The only explanation that makes sense to me is that they were all incapacitated at the moment of catastrophe whilst still in the cruise.
Now, what to infer from that? I have absolutely no idea and I would suspect that no-one else has either.