I was looking at this from the point of view of a human body traveling 100 mph'ish inside of a steel box and decelerating to zero in a fraction of a fraction of a second.
True. The spring would only slow the descent at the last fraction of a second, which is why it always looked useless to me. However, the fact that it was there would indicate, along with the age of the building, that there was no braking or other safety mechanism. I think the building was built in 1933 and Eleanor Roosevelt had once occupied the penthouse...