[Moonman62]

SKY News: Aviation journalist Anthony Davis says the Airbus A320’s rate of descent was “unprecedented”, suggesting a “catastrophic” event of some kind.

...

Flightaware shows it was close to a normal descent, but unplanned, of course.

[Robe]

Lets do some math...
Cruise alt =39000ft(approx),
Impact Alt 6500ft (approx),
total Descent 32500ft(approx)
10min (approx)from cruise to impact
That comes out to about 3250ft per min decent
Normal descents are about 500 ft per min

Over 6 times the normal decent