I think there's also an unrealistic or crazy expectation of how much space individuals need. My great-grandparents raised five children in a 2 bedroom 1 bath house house - well really 6 since my great-grandmother basically raised my mother until the age of 12. I grew up in what was originally a 3 bedroom, 1 bath house. My step-father had to build a wall up the middle of my bedroom to stop me from murdering my little sister who kept getting into/destroying my stuff. The family across the street from us had three kids in a two bedroom house and those bedrooms were very small. The house I currently live in is 3 bedrooms 1 1/2 bath. The family we bought it from owned it from the 1940's until we bought it in 2014. But, they also raised 4 kids in this house. The basement looks like it was once a rec room and that is where the 1/2 bath is. And even in this house - the two smaller bedrooms aren't that much bigger than prison cells - probably about 10x12, and two kids lived in each of them. But, now people think that each kid needs to have their own room and their own bathroom, there needs to be dedicated teen space, the dad needs a man-cave, the mom needs a she-shed. I mean really? WTF? Most people for the entire history of the world did not have this kind of personal space unless they were super rich. I mean where did this sense of entitlement to all this space come from? Growing up - lack of personal space/peace and quiet in the house was just incentive to spend as much time as possible OUT of the house.
I live now in the 1920's house where I grew up. Back then we had 2 bedrooms and one bath. All our rooms were bigger than those in the houses around us which also had 2 bedrooms and one bath. They were mostly built for returning G.I.'s. Virtually all of them are mini mansions now.
My dad made a clever floor to ceiling divider in the room my brother and I shared. It included compartments to hang things up and with shelves. Our new rooms were small and strangely shaped to each include a door and windows.
After he died my mom paid for a big addition so I and my family could move in with her. It gave us two master suites, a laundry room, an office and an attached garage. My two youngest step-daughters needed separate rooms. We and my mom needed ours and our bathrooms.
So I totally get what you're saying and I also get why everyone who can afford it wants 4 bedroom, 3 bath houses like ours. Dedicated teen space, a man-cave, and a she-shed are luxuries we never needed, nor a "play space" for the younger kids. All our toys fit in our bedrooms.