Couldn’t they do dorm style with shared bathroom facilities? Usually office buildings have much better ventilation than private residences.
And it doesn't really matter what any one person would or wouldn't want to live like. I wouldn't want to live in a 200sqft apartment in NYC, but apparently a lot of people are willing to pay a lot of money to do so.
The correct question is if homeless people sleeping on the concrete - would they want to live in that. And probably a good many of them wouldn't.