I’ve been to the USS Bowfin, and really got a feel for the close quarters there. The fire control center in the conning tower held 4 people at least during an attack, and is smaller than most modern bathrooms.
Imagine living in a fleet submarine like the Bowfin or Pompanito for 2-3 months at a time. If you didn’t like a shipmate, it could get real hairy towards the end of a cruise.
I cannot imagine living on a sub...I can’t even walk through one without panic setting in and the walls closing in around me.