>I probably also wouldn't equate "a person with an ADRB1 mutation can sleep less" and "a single individual that underwent brain surgery can sleep less" with "Decreasing sleep by 1-2 hours a night in the long-term has no negative health effects".

I made 5 points in that section (https://guzey.com/theses-on-sleep/#decreasing-sleep-by-1-2-h...):

> 1. A sleep researcher who trains sailors to sleep efficiently in order to maximize their race performance believes that 4.5-5.5 hours of sleep is fine.

> 2. 70% of 84 hunter-gatherers studied in 2013 slept less than 7 hours per day, with 46% sleeping less than 6 hours.

> 3. A single-point mutation can decrease the amount of required sleep by 2 hours, with no negative side-effects.

> 4. A brain surgery can decrease the amount of sleep required by 3 hours, with no negative-side effects.

> 5. Sleep is not required for memory consolidation.

You cited (3) and (4) but ignored (1), (2), and (5) all of which are based on studying dozens and hundreds of people.