The virtual ESC key on the MacBook Pro with a touch bar has much to be desired.
It can be made slightly better by increasing the size of the ESC key using Better Touch Tool.
Open the Better Touch Tool Configuration.
Create an Iterm2 App (because I only care about the escape key when in a terminal window).
Add the button and assign a title. In this example the button is called: THIS IS THE BIG ESCAPE KEY NEEDED TO MAKE VI WORK
Assign an action to the button: Keyboard Key -> Escape
The button will look like this:
Note: It is not the most responsive button. It sometimes takes multiple presses to recognize a press.