Apparently I'm merely a casual vim user, but I would struggle without an esc key.

An apparently serious vim user here.

You shouldn't be using the escape key because it takes your left hand off the home row. I prefer the Caps Lock mapping to the 'jj' variant which might make be more work for my pinky and be slightly slower but it works for me.

Having easy access to your mode switching character is important because training yourself to enter Normal after entering a piece of text is the first step to 'next level' Vim use.

For you GNOME users, making your Caps Lock an escape key is as easy as setting it in the Tweak Tool.

Huh, guess I'm a serious vim user! I've got Caps Lock as the escape key, and shift+escape as Caps Lock.

The biggest downside is that if I'm using someone else's computer, I keep yelling for no good reason.

Wow thanks for this, didn't know about the alt trick