Yes, the old diesel boat sailors lived in much more spartan conditions. Having a nuclear reactor meant we generally had plentiful electricity and steam, which enabled such things as a bigger hull, better lighting and a better ability to make more fresh water. Fresh water was still a precious commodity on our Permit class boat, but not so rare and dear as it was for the ol' diesel boats. Air conditioning and precipitators made for better air, but we still had a marked aroma when we got back from sea. There was no escaping the atomized hydraulic oil and (back then) cigarette smoke in the air, but I'm sure it was worse for the diesel boat guys.

If you ever get to the Groton / New London area, tour the submarine museum and the U.S.S. Nautilus which is tied up there. The Nautilus was basically a diesel boat hull converted for a nuclear reactor propulsion system. So you still have somewhat tighter quarters, but many of the improvements that nuclear power enabled. The museum has the twin screws from my one-of-a-kind design sub, the U.S.S. Jack, there as well. We were a Permit class sub, but we had a unique propulsion system.