Not a surprise at all. When I first started driving autos were 3 or 4 speed slushboxes which were slow and poor on fuel. You only got an auto if you were elderley, drove a huge executive barge or didn't have the skill to operate a manual gearbox.
Now we have cars with 7 speeds that can shift in the blink of an eye and offer better economy and acceleration than any manual. They probably would have been adopted quicker if it hadn't been for the terrible image problem that old autos had.
I still often miss the enagagement of driving a manual though.