I still use the mouse from time to time when editing text mind you. But for most actions, I would not think of moving my hand to the mouse, because it is slow.

Even before vim, I made gratuitous use of end of line navigation via keyboard (home/end buttons; cmd+arrow keys). vim is just a more powerful version of those buttons.

I make no claim that vim is the MOST efficient platform ever created, but it's a lot faster than mouse+keyboard and/or out of the box editing methods.