Try to learn using "Ctrl + [" instead of ESC. It helps.
Eventually, I got used to ESC. I move my hand more than bend my wrist, so it isn't so bad. I hit ESC with my left ring finger. I also try to plan my next keystrokes and/or move my right hand into next position while my left hand reaches for ESC.
I've found that moving ctrl to the capslock key also helped reduce wrist motion, though it makes using other people's computers more annoying, since I try to do everything on the keyboard with pure muscle memory.
https://upload.wikimedia.org/wikipedia/commons/a/a0/KB_Termi...
My computer use is so dependent on muscle memory that I can't comfortably use anyone else's computer, even without the moved keys. Every time I get a new computer, there is a long adjustment period too. I find the trade-off worthwhile though, since I'm rarely far from my laptop and rarely type more than a few sentences on other computers.
It was a fascinating set of key bindings, but a problem with it was that it wasn't very portable, and I hit too many problems with Vim modes in other editors not supporting rebinding Tab or causing too many accidental side-effects.
(I try to keep CapsLock bound to Backspace so there is a Backspace on each hand. It's a good use of the key. Though maybe real Backspace might make a good, Esc in a Vim binding, hmm, I'm going to think about that now.)
" In insert mode use 'jk' as Escape key
:inoremap jk <esc>Go to System Preferences -> Keyboard, then on the lower right, click the Modifier Keys button.