Linux

That's not true at all. I used to have pain in my wrist and went very heavily into keyboard centric usage. At the time I used AwesomeWM and Conkeror for a full keyboard centric OS, I also learned to touch type in Colemak at this time and bought a trackball. Eventually I started using PyCharm instead of Emacs, and Conkeror was abandoned so I switched back to Firefox, I switched to i3 for their better philosophy on monitors and workspaces, and switched back to a mouse for better aiming on games, and now I have lots of stuff that use mouse, but the pain never came back. And the reason is that while it is true that I still use the mouse, it's much less than I did before, the vast majority of the time I can be programming, run something in a terminal, go to the browser and do a quick search, send a message to someone on slack and go back to my code without touching the mouse. Sure, if the result of what I was looking for is not on the front page I'll need the mouse to click a link, and if the person on slack is not the one I was last talking I'll need the mouse to click his name, but those are two possible mouse movements for a full workflow of stuff that would have needed 6 or more mouse movements before.