The first house I lived in had a kitchen ad living room on the first floor. We ate in the kitchen, even when company came over. The living room was where we watched TV, I played with toys, where my mother ironed.
When I was 7 we moved to a house with a living room, dining room and kitchen. The living room was never used, it was for when company came over. We had a finished basement where we gathered to watch TV. When we kids were small we all ate in the kitchen, eventually we moved to the dining room as the kitchen wasn’t very big.
It wasn’t a formal dining room though, it was attached to the kitchen.
When company came over the adults ate in the dining room and the kids ate in the kitchen.
The basement room also had a bar and fridge for when my parents had parties. We also had a ‘pool’ room which was where the pool table was kept. It wasn’t finished though and any time a ball got knocked off the table somebody would have to fish it out of the sump pump. YUK!
Now the part of the basement that was the bar is a bedroom and the other half is a sitting room, and the pool room has become the junk storage room.
Our dining room was also where we did homework, played board games, sewed, did crafts, wrapped gifts and where my parents did their bills. etc.
Part of having all those separate rooms is being able to do one thing in a room without having to pick everything up to do something else. If you have a study with a desk you can keep all your bills and stuff in there. I hated when I was in the middle of sewing something and I’d have to stop in the middle and pick up everything and put it away so we could eat dinner. Then pull it all back out when dinner was over.
If you have a rec room you can have a TV, toys, exercise equipment, game tables and stuff in there. By having a family room or rec room your living room isn’t always cluttered up and stays presentable for guests.
If you have a rec room when you do have guests the kids can congregate there and leave the adults to the living room.
If you entertain a lot you may want a separate ‘formal’ dining room, which is a separate room from the kitchen, to serve dinner. As opposed to just a dining room (area) which is attached to the kitchen but not a separate room.
Dens, studies and offices are traditionally where the man of the house went to escape and do manly things.
I’ve seen newer houses that don’t have living rooms at all, or they are so small as to be worthless.
Family rooms are often attached to the kitchen so whoever is working in the kitchen can keep an eye on the kids and/or talk to their guests.
Not everybody uses the rooms the same way though. What was the formal never used dining room in my friends house was used as a bedroom in another friends house.
That is where lifestyle comes into play as to how the rooms are used.
People with more money tend to have single use rooms as opposed to multipurpose rooms.
When I lived alone my dining room was my sewing/craft room. I could probably count on the fingers of one hand the number of times I ate a meal at the table. If I had been a family I’m sure it would have been used as a dining room.
If I had to pick just one, probably the living room, but if I was married with a whole mess of kids I’d want the family room attached to the kitchen.