I'd lose my mind in a house that small. Our family needs a lot of room. (Originally 5 people, 2 dogs, tons of books, and stuff.)
We've rented cottages while on vacation, but most of them were bigger than this house.
And that ladder may be OK for a young, single man. But, it would be dangerous for a pregnant woman and children. Also, I'm a "four burner" cook, and I bake a lot, so I need two ovens, the one I have isn't even enough. I couldn't get by with a toaster oven. And, where is the storage for the sex toys?
However, this man, who builds these "tiny houses" and lives in them seems really happy with them. I think it's cool for him.