I am not dismissing the research and I am well aware there are tradeoffs. I am aware that low sleep puts extra strain on the brain and the body at large. I am aware of the increased inflammation, decreased CSF draining, cardiovascular issues, appetite issues, insulin tolerance etc. etc. I know that our bodies were optimized by evolution to function better with sleep cycles synced with circadian cycles, and I know that many of these very well optimized processes are put under stress when you sleep less than 6h per night.

Here's the thing: say what I have is a "disease" and currently, the best cure for this disease is a pill that would slow down my thoughts and make me into a bland emotionless vegetable during my waking hours in addition to reducing the amount of waking hours that I get to enjoy. Even if that magic pill buys me 20 extra years of old age at the tail end of my life, is it rational for me to take it in my early 30s?

When I was looking into the dual n back stuff a while back, I remember reading one report where the person would feel subjectively fine when sleep deprived, but his nback score would go way down.

In other words it's possible to "feel fine" on little sleep and yet be significantly cognitively impaired. Worth measuring that, if possible.

(It might have been Gwern, he's got a big page on the subject.)