Ironically enough your example is flawed: there are documented 10x touch-typists.
The realities of the court system place high demands on the typists; the minimum required typing speed is already quite high: trained court reporter or closed captioner must write speeds of approximately 180, 200, and 225 words per minute (wpm) at very high accuracy in the categories of literary, jury charge, and testimony, respectively[1] - and some exceed the minimum and go for 300 wpm. Even better, the official record for American English [is] 375 wpm [2].
Compare that to the average typing speeds around 30 - 40 wpm [3] Granted, the court reporters use specialized input devices (stenotypes) - but hey, the same can be said about highly productive programmers, who use specialized development environments - and sometimes also specialized input devices.
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[1] https://en.wikipedia.org/wiki/Stenotype
[2] ibid.
I've had good luck discussing the subject back in 2013: https://news.ycombinator.com/item?id=6464807 and https://news.ycombinator.com/item?id=6465175, with the insightful replies.
Wow, reading the discussion from back then shows how much HN changed in spirit.
The more software development work approaches touch-typing, the less difference between 1x and 10X — strict Jira tickets in, garbage out, maybe slightly faster. Spec-work, and most grunt-work, is undifferentiated and does not benefit from a 10X person. The more your work approaches poetry - such as exercising user empathy, improving the architecture, considering UX, respecting performance constraints, understanding user's jobs to be done, and improving your implementation around that - the more creative space there is for 10X to reveal itself.