Earlier quoted context omitted.
For those of us who can type very quickly, every movement of the hand away from the keyboard (to the mouse) and back has a high cost in terms of lost typing opportunity. If speed and subconscious operation are the goal, then it's best to stick to as much keyboard only as possible, or alternately to learn to maximize the one hand keyboard + mouse approach (which can actually be very fast once you know your tools).
For most of us mortals, typing is not the bottleneck when we are writing code, an article or whatever. In any case, keyboard-only interfaces make the assumption that you know all of the shortcuts for each program you use. And boy they are inconsistent. They also offer zero discoverability for someone that did not read the manual (see the vim jokes). I like software that offers both good pointer UI + robust keyboard s…
That's why you carefully choose programs that are highly configurable so that you can integrate them seamlessly into your particular workflow.
The reason I use Emacs is not because it's a great editor. It's slow, often frustrating and since adding LSP support it crashes frequently. The reason I stick to it is because it gives me endless customization so that I can decide how I want it to work, instead of the author or some company deciding that for me. Learning to use it is therefore an investment in future time saving since I won't have to worry about it drastically changing or moving to another system if the company that supports it decides to change direction.