C-a is the worst default keybinding ever, since like, going to the beginning of a line is one of the most common operations.

Well, not with proper key bindings ;) (set -o vi)

In the rest of the universe, going to the beginning/end of the line is mapped to the Home/End keys (fn+left/fn+right on Macs), and I do prefer it when my thing does things in ways that roughly correspond to how the rest of the universe does them if there's no compelling reason to do otherwise.

> (fn+left/fn+right on Macs)

When I used Mac in 2009 to 2012 it depended on the application you were using:

Some used fn+left/fn+right, some used CMD+left/CMD+right and I think ctrl and/or alt + arrow keys were an option too.

ctrl a/ctrl e would work everywhere I think but I didn't use those as they didn't work with shift to select to the start or end of the line.

As a keyboard type of person this was a major part of what drove me away from Mac despite its many advantages :-(

Caps lock isn't shift lock though.

I know, because I have triple-shift-press mapped to shift lock on my Ergodox. It's... usually better, but sometimes I type a @#$%@#$% swear word when I mean to enter a number.

I have remapped capslock to be an additional ctrl so I hit C-z easily with my pinky + ring fingers.

C-a (like in screen) would be even better but as others have pointed out it masks going to the beginning of line which is very common.

C-z is very rarely needed. C-q/C-s would be good candidates also as I don't think I've ever needed flow control in this century nor the last one, for that matter.

> And you say z is close to control - does that mean you use emacs without shift lock as control?! (I mean sure, still closer than b...).

Presuming Shift Lock means Caps Lock, that and Control are both close to Z on my (Apple) keyboard.

I use ctrl-a quite a lot on the command line, though.