It's not about bravery or being a wuss. We all want different things from nature.
For most people on most days, 5pm means dinner, couch, TV.
Then you get tent sleeping that could turn into a Sensory deprivation chamber, a solitary prison cell, because while we have many trail miles logged, we have much more couch sitting hours logged.
When there is a trail buddy, we have philosophical conversations about life, family, religion, politics, while taking time lapse photography. One trail buddy likes to drink whiskey, but on another trip another buddy goes to sleep early at sunset, because it usually was a long day with little sleep the days before.
When I'm solo, I don't let brain stimulus happen organically at random, I set myself goals and tasks to do and think about, to keep my mind occupied, until I fall asleep. Perhaps sunset photography, spy on night wildlife, develop a plan for world peace, plan future wife bribes to promote future solo outings and plan for career change and early retirement.
By the time I get 45 mins into this mental exercise, I'm snoring. At home I have insomnia.