Just read a disturbing article on this term while research on Hong Kong. A significant proportion of low income families or singles live in these coffin homes because rental has simply gotten too expensive.
Coffin homes are becoming a way of life in HK. The pic above shows typical single man living in his coffin home. The pic below shows a small family living in a slightly larger room.
Families living in a "bigger coffin" spend their time in confined space studying. The picture below shows another family having a meal in their coffin room.
Here's the punchline: is this also the reality Singapore is facing?