I use emacs now with a highly configured set of key bindings, and you're right it's taken me a lot of time. You're comment makes me think there are two types of programmers, those in the "don't make me think" school and those who spend an insane amount of time in one of the big editors, i.e vim/emacs/sublime. To make a gross example of the deficiencies of each, the "don't make me think" school are the people who would manually enumerate function calls instead of learning what a for loop is, while the crazy emacs hackers are the type to spend more time fine-tuning their config than actually working.
Whether or not the 10x developer is a myth, there are people who are vastly more productive than others. And they are people who have invested in themselves and their skills, automating away everything they possibly can.
After some time, it all become muscle memory.
I haven't used an install of Vim in a _long_ time that didn't map the arrow keys (and home, end, pgup, etc) to the way most modern computer users are used to.
I use Vim because it's what I learned when I first started using Unix/Linux. It's on just about every machine I work with and is easily installed on anything that doesn't come with it out of the box. I'm not arguing that it's the best ever editor, just that it works well for me.
But, yeah, the days of having to always use hjkl to move around are pretty deep in the past at this point.