Those people should try serving three tours on a submarine first, and a few winters in the Antarctic, after.

My guess is, that short list of volunteers will get a lot shorter.

The difference isn't being stuck in a metal tube, it's being able to see space. See stars/constellations etc in person. On a sub you don't get to see anything. And I haven't heard much about the views from Antarctica.

You're not going to be seeing very many stars there, either. Your tin can's not going to have much in the way of windows.

Some of the Starship renders images published show extensive windows.