Yep, claustrophobia. And really, considering the canon sizes of the ships, even the larger ones probably should have appeared smaller on screen. After all, most of us live in rooms that are about 10 feet high, maybe 15 feet diagonally or so (small bedrooms are often 9 feet by 9 feet). 3 feet is a little less than a meter.
Even the 2009 Enterprise
is 610 - 910 meters (http://en.wikipedia.org/wiki/Starship_Enterprise
), or around 1976 - 2948 feet. Even with standard small bedrooms, that's 220 - 327 of them on the entire ship (I can't recall how large that crew was, but there were more people than the 90 or so on the NX-01
), with no room whatsoever for engines, the bridge, sickbay, any recreational facilities, an armory, cargo storage, transporter room, etc. Doubling people up in such tiny spaces is possible but that would show even more claustrophobia.
It is possible to fit in everyone and everything, but even on a ship of that size, it should have seemed a helluva lot tighter. Enterprise
absolutely gets this feeling right, I feel.