For "no apparent reason"? ESC is incredibly non-ergonomic. If you use vim and don't use capslock or jj you're setting yourself up for RSI.
The use of vim requires neither the use of the Escape key nor key remapping. I'll leave the "how" as an exercise for the reader, it should be quite discoverable (discoverable for vim, anyway).
If pressing Ctrl+[ is your alternative and you prefer to press two keys instead of one then we are definitely not in the same group of people, I don't even considered an option.