While I agree with everything you say in general and I'm a confident advocate of "you should get more sleep!", I find it hard to condemn people for specific cases.
I need 8.5 hours of sleep per night to function properly, and the effects are very noticeable if I get reduced sleep for more than a couple of days in a row.
At the same time, I know several people who sleep 3~6 hours per night and I will not convince them otherwise: One suffers from insomnia for as long as he can remember and has effectively adapted his life around it, and another genuinely feels rested and is unable to sleep more.
We're all different with different needs, and we need to take that into account. But unfortunately most people don't pay attention to their needs and walk around like zombies five days a week, or worse.
People tend to overestimate their own abilities and performance.
Especially when they're operating in an impaired state: drugs, alcohol, fatigue, or cult-like communities (which often combine all of the above and then some).
This is very well established in literature particularly regarding management and business:
I can honestly hardly believe the 3- to less-than-6 hours figure if it constantly is less than 4 or 5 per day... studies indicate that this, by and large, is where it WILL start having impacts but of course there could be exceptions and maybe there is a kernel-hacker gene!
I need 8.5 hours of sleep per night to function properly, and the effects are very noticeable if I get reduced sleep for more than a couple of days in a row.
At the same time, I know several people who sleep 3~6 hours per night and I will not convince them otherwise: One suffers from insomnia for as long as he can remember and has effectively adapted his life around it, and another genuinely feels rested and is unable to sleep more.
We're all different with different needs, and we need to take that into account. But unfortunately most people don't pay attention to their needs and walk around like zombies five days a week, or worse.