Whenever the conversation of space for people on ships or space-stations comes up we trot out Earth norms and say "see it is fine". Except that those norms for living spaces on Earth are very deceptive. How many of those Germans stay in their home 100% of the time for 10 days or more? Never leaving or interfacing with the various spaces outside that home? I live in a family home of just over 1000 sq ft and there are four of us here. But I get to walk out into my back yard whenever I want (not counted in that sq footage). I can walk up the block and have a snack at the local fast-food location (not counted in that sq footage). I can get in my car and drive over to the local mall (for sure thousands of sq feet and not counted in that 1000 sq feet.) and walk around shopping or dining or whatever I want. I never, ever stay 100% of the 24 hour day inside my house. So is that 1000 sq feet really fair?
People like to use cruise ships and point out how small the cabins are. But what about the thousands of sq feet dedicated to other uses? Pools, restaurants, theaters, shops, etcetera? You do not go on a 10 day cruise and then stay locked in your cabin the whole time.
Ok, I will stop because I get my point of view is not the majority in the Traveller fan base. The norm is to min/max the engines and weapons and who cares about the crews, hell let them hot bunk in hammocks strung three high in a storage closet.
These points definitely apply to permanent residents. Where you decide Travellers should be will depend on your game concept. If you are thinking sleek Star Trek Next Generation accommodation with swathes of room you will come up with a different answer than if you thinking Serenity.
You could allow for that flex by specifying all accommodation in terms of SOC (much the same way we define cost of living). The crew of the Serenity are at best blue collar workers. They are definitely scraping by and even have minimal common areas (we even see the cargo bay being pressed into service for recreation). The Star Trek crew we see clearly have a high standard of living but they are clearly in a post scarcity society. They can replicate anything and their holodeck is effectively infinitely large.
Every ton of space you dedicate to people is a ton less you can dedicate to making the ship pay for itself. Those large areas on cruise ships are because the ship is the thing people are paying for. People on cruises are not travelling to get somewhere. The cruise is the end in itself. One complaint of tourist destinations is that cruise passengers rarely stay long enough to experience the culture of the place they are supposedly visiting and don't really spend enough money there, most of their money has already gone on paying for the ship and all those entertainments you mention. A lot of it is also shopping and those retail spaces pay for themselves.
There is a tie in to TL and accommodation is one of the few things that do not have TL tiers. Back in the day when you lived in a log cabin, you were so busy buying food and working you didn't need space for your recreational needs as you didn't have much downtime. Even in winter when you couldn't get out much as you were mending and repairing (and possibly starving). My grandfather used to grumble that in his day "we made our own entertainment". My life is still physical, my house is stuffed with things I have acquired as my early life meant the acquisition was a lengthy process and I developed a hoarder instinct. Now I can buy stuff from China with pocket change that I would have had to save for months for. I am still storing all that crap, but if I was born into that lifestyle I would probably be one of those people who seem to change their car when it needs a service. My entertainments were books, models and electronics all taking up their Dton of storage. I suspect my children will keep far less stuff than I do and their entertainments seem to be rented and based on a mobile phone. If they had a holodeck they would probably never leave it.
Traveller needs to be able to reflect both extremes and anything else the referee an players want to explore. It needs to be a framework for YTU. Fixing ships accommodation at a pre-conceived level and then fudging the number to say it includes x or y without actually considering the implications of that stores up trouble for the future and makes the referees job harder rather than easier.
So I would calculate the minimum space required to exist and have it multiplied by a function of SOC (the richer you are the more stuff you want to have). Then divide it by some function of TL with early TL meaning lost of physical things and later TLs being able to simulate physical things or to replicate them on demand and recycle them when no longer needed.
The referee is then able to tailor the accommodation to match his concept of the vessel in question. A low TL (and therefore likely cheaper) vessel for working stiffs will have cramped accommodation and maximise the ships profits (but they are going to have to carry more passengers who being cramped are likely to have more stress and therefore risk of incident). Or he can have the sector Dukes son flitting about in a top of the range vessel where even the assistant chef is a baroness and absolutely cannot share accommodation darling and must have space to declutter her mind before creating her next masterpiece desert.
... and for the military you might need to hotbunk. Since you are on duty half the time why should, that pit sit empty where we could put more torpedos!!
And to be fair during 2020-21 I spent the vast majority of my time in my house. I did not kill anyone, we spent more time as a family playing games and doing joint activities than at any other time before or since. Our house is UK typical 4 bedroom (12 Dton in traveller terms - slightly over half of it common rooms and access). Our occupation of it is not typical we have a whole room full of re-enactment gear (in theory a spare bedroom, but you can't get to the bed) it is also full of the clutter accumulated by a 50 year old hoarder who has more hobbies than time to conduct them and the attention span of a butterfly.