Because "why don't the tools learn me" describes a perfect world, a fantastical end state worth working toward, but which we just don't live in yet. It's akin to questioning why we still bother with locks on doors when burglary and theft are solved problems in a post-scarcity society.
I'd love better design, UX, and discoverability in all software tools everywhere, but the grim reality is that this just isn't the case and won't be for many years. Until then, I can say again from personal experience that it was well worth it for me to Google the keyboard shortcuts for terminal cursor movements, greatly reducing friction between me and my filesystem. Similarly, occasionally bringing up the VSCode or RStudio keyboard shortcuts reference windows is well worth it to reduce the friction between my thoughts and my results. It's like going from hunt-and-peck typing ("why can't the input device just learn how to understand my speech?") to touch-typing faster than you can write by hand.
Come to think of it, resistance to plentiful keyboard shortcuts is not something I would have expected to read on HN of all places, yet here we are!
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