Not sure about emacs (I use spacemacs). Does esc come in for more than just cancelling commands? If you don't need to use your caps lock for ctrl for emacs, the same remap to esc would work as well.
Anyway, basically boils down to two things: 1) the touch bar escape is fine for occasional use but I wouldn't want to use it frequently and 2) that isn't a problem if you don't mind remapping caps lock and have nothing more important to do with it.
evil-escape module for evil mode adds the 'fd' functionality discussed here.
if we use carat for cursor,
this is a line of text
^
typing ft does this is a line of text
^
whereas tt would this is a line of text
^tl;dr: If you, like me, touch-type and work very fast, then the absence of tactile feedback on the new Esc is unnerving. It's like a work-stopper. Even if something did happen when you hit it, the lack of feedback means your brain automatically thinks you didn't hit anything. I don't know if this is something one gets used to. After a week, it's still awful.
(because they decided not to make one, actually)
Apparently they did actually consider making a car, which I didn't know.
When you consider what the keyboard layout on the machine on which vi was made looked like: http://xahlee.info/kbd/i/vi/terminal_ADM-3A_keyboard.jpg , it's easy to understand why dual-use caps-lock makes the usage feel smoother and more natural than on regular PC keyboard layout.
For anyone that would like to do this, here are example instructions for both Linux and MacOS: http://www.economyofeffort.com/2014/08/11/beyond-ctrl-remap-...