We'd see lots more cases of flyers getting into more trouble if there was a 1000 metre limit.
We already see plenty of cases of flyers that go up 1000 ft or more and have their drone blown away because they don't understand how high level winds can be very different from what they experience at surface level.
Without a 1640 ft limit, we'd see even more drones blown away.
Descent time and battery life is another important factor
If you climb to 1640 ft just getting down requires 2.8 minutes but if you went twice as high you now need 5.6 minutes just for a max speed descent
DJI have given you the ability to fly to 1640 feet above launch point and that is more than enough for most people, most of the time.
The number of times users would be inconvenienced by a limit of 1640 ft above launch point would be very small.
If you have a real need to climb higher, there are other drones you can do it with.
Descent time is around 2 minutes in sport mode.