As someone whose computing career was improved by learning to touch-type in grade school (Mom had been a secretary, saw that these "personal" computers had keyboards, and bludgeoned the high school to let me in to the summer-school typing class) it's not actually the speed that matters - though that does certainly impress people - it's that it's "automatic". If you're not thinking about letters and where they are, you aren't distracted from the entire sentence (or function) you're holding in your head - it just pours out through your hands into the machine.
(Sometimes I joke about how my hands know emacs, not my brain - but if someone asks me what keys I hit for something, my fingers move and then I work backwards from that.)
(And if you're collecting correlations - I have no musical performance talent at all and have spent maybe 10 hours total poking at musical keyboards - for me, typing is all typing, I expect musical keyboarding is a related but parallel thing, not the same thing.)
I feel this in my soul. My work uses Mac and I'm not used to it. Fn and cmd keys block my reach for alt and control in my vim sessions and make it awkward to go through tabs in the browser with the keyboard.
Fun fact : I have an external keyboard, but it's an MS one, so there is no more drivers, and some keys just won't work (or at least I haven't yet found anyway to remap things.)
I'm an oldster who just got a split ergonomic keyboard for the first time a couple of weeks ago. I'm going through the exact same experience. It's getting better, but my typing/coding speed has been cut in half as I unlearn bad typing habits accumulated over the decades.
Had the same issue recently, with the caveat that I grew up in the UK, then moved to US and back.
I prefer the concept of international standardisation to an American layout in pretty much all areas, with the exception of the keyboard layout; ANSI layouts are far more friendly - for programming, at least. Not just the enter key but the left shift too.
Switched to US layout on everything (because brackets and gt / lt are SO much more conveniently placed) and having to use an ISO keyboard now is just pain. My hands forgot.
(Sometimes I joke about how my hands know emacs, not my brain - but if someone asks me what keys I hit for something, my fingers move and then I work backwards from that.)
(And if you're collecting correlations - I have no musical performance talent at all and have spent maybe 10 hours total poking at musical keyboards - for me, typing is all typing, I expect musical keyboarding is a related but parallel thing, not the same thing.)