My nephew likes subs for the small crew and the challenge. I do know he has been "hot racking", two bunks for three men, in shifts. He doesn't seem to mind.
Carriers are huge. My dad served on carriers and loved the many port calls. He was with an air squadron though.
It is a myth that the sailors make the choice. They can list a preference for one or the other, but like everything, it depends on the needs of the Navy at the time they finish their school. Just like they list preferences for their first duty station, but again, it is the needs of the Navy.