The figures I remember:

In the 1950s, new homes were 1200 sq ft or less and held an average of around 3.5 people. They are now over 2400 sq ft and hold an average of around 2.5 people. They also now come standard with AC, dishwashers, washer-dryer hookups, etc. In the 50s, AC was not standard, dishwashers were not standard and many homes had a washing machine but no dryer. The norm was to have a clothesline in the backyard.

I have been in a house like that. My ex husband's grandparents lived in such a house. It was a two bedroom, one bath place with a washing machine and a clothesline. Dishes were washed by hand in the small kitchen. They had ceiling fans instead of AC. This was in Georgia, where AC is very much expected today.

They raised two kids in that house. The kids shared a bedroom.

So, families have grown smaller. Houses have grown larger and more luxurious. It is nearly impossible to find a small house with just "the basics." That is now considered substandard housing and most jurisdictions in the US have zoning laws that make it illegal to try to recreate 1950s style housing.

The New Urbanism movement actively tried to recreate walkable communities similar to what we used to build. Any New Urbanist project that got built typically went in with a plan, was told it was unbuildable because of zoning laws, road width requirements, etc and then they combed through local laws and regulations and renamed things to try to get it okayed with minimal changes to the actual design. It was an uphill battle every step of the way to try to recreate something akin to 1950s style housing with small homes and a walkable landscape that wasn't completely whored out to a car centric design.

The Tiny House movement puts a lot of small houses on wheels to get around minimum house size rules. And then good luck finding a place within city limits to park it. The city of Fresno recently passed a law to try to make it easier to have a tiny house. The law assumes it will be an accessory building behind a larger conventional house. It basically assumes that it is a stand alone "mother in law unit." The assumption is some relative will live in it, though you can potentially rent it out as well. Tiny houses become glorified upscale trailers. You can live in them in the middle of nowhere and you can tow them behind your truck, but trying to find land to place one legally within city limits anywhere in the US (as a primary residence) seems to be quite the challenge.

Apple Valley, California has a huge minimum lot size for houses that was theoretically supposed to "preserve the rural character" of the town. No, the result was not farm houses with large vegetable gardens. The result was huge houses on huge lots. Driving through a residential neighborhood in Apple Valley is a fascinating glimpse into how our housing regulations so frequently have unintended consequences.

I just want a small home in a walkable neighborhood. I don't need or want AC. I don't need or want a dishwasher. I would be happy to have a washing machine and a clothesline. This style of housing is no longer built.

If you can find it at all, it was built between the 1920s and the 1950s. Such homes tend to fall into one of two categories: they have been improved and kept up to date and are now some of the most expensive real estate in the city in high demand, or they are falling apart and in a neighborhood that looks like a war zone. You may be required to bring everything up to code before you can move in.