I would even argue that being surrounded by people is a natural state. Being isolated in a suburban home or an automobile is probably just as unnatural as being “surrounded by strangers”.

Our ancient ancestors probably did all of the following within eyesight and earshot of around 40 people:

  - Eating
  - Drinking
  - Defecating
  - Fornicating
  - Bathing
  - Exercising

Privacy and isolation are a very modern phenomenon. Even in the 19th century social norms around fornication and defecation and the privacy expected are much different than today.

Edit: I’m also deeply fascinated by the ability of historical sociolinguistics to give us insight into cultural attitudes towards different topics. Consider the evolution of and the attitude towards the expletives “fuck” and “Jesus Christ!”