Do you really need to know other kinds of sleep in order to know if you feel like shit after waking up or if you feel fine?

They're probably also less confronted with articles/videos/social media posts telling them they're doing it wrong and how they should sleep instead. Sometimes ignorance (or rather, not overthinking things) is bliss...

Also, they may not want to complain to strangers.

Also, we humans can get used to a lot of things and just be okay with it. For an extreme example, look at domestic abuse victims...

Well probably us modern human only know the "8h sleep at night" kind of sleep, yet a lot of people would tell you whether they're satisfied or not with their sleep