For living arrangements, you are mostly correct. I can exist very comfortably in about 1,000ft². Heck, even 800ft² would be comfy and cosy.
My problem involves my hobbies and domestic activities: I need a 200ft² cool room for the enormous amounts of fruits and vegetables I harvest every year, canning all that shit needs a 150ft² summer kitchen so I don’t seize up my regular kitchen with all that processing (I use that summer kitchen consistently at least six months out of the year), I need a library the size of a master bedroom (at least another 200ft²) for my books (including the movable stacks on rails), I do enough woodworking to need a garage-sized shop (500ft²) , and my IT work requires no small office (180ft² and an attached server room (80ft²) with its own cooling. Plus, I regularly use a wet sauna, which needs the same amount of room as a laundry.
So that balloons my requirements by _at least_ another 1,500ft², to say nothing of the needs of my wife.