As someone who does need 8 hours I can't help but be jealous of those who function on 6. If I only get 6 hours of sleep I can't even see straight all day.
Don't be. Hell I can "function" with my shoes tied together.
I can "function" with some marijuana and some whiskey in my system.
I can "function" on 4 hours of sleep. It's an awful day and I'm more rude and impatient, but if I did it for years I'd be telling people I can fully function on 4 hours with no negative side effects.
Now notice that the current US President has been severely sleep deprived every day for decades.