The photos show a lot of very well-thought-out uses of space. Use and efficiency is the key, rather than absolute size.
I raised 3 kids in a 16 x 20 ft log cabin. We slept up in the attic, under the peak of the roof, reached by a ladder and a trap door. We had no plumbing or electricity. We were also 15 miles from the nearest road and could only get to our home by boat or float plane. It was wonderful and I loved it, particularly the part about having no electric
lights. Song and story flourish when you can't keep your daytime activities going until bedtime.
As an older person, who lives in a very tiny space, I would caution that extremely small size can be very limiting and counterproductive for a homesteader. There was a reason that traditional farmhouses had some size to them--not McMansion size, but enough space to get work done and keep essential tools and stored food under cover. In our current space, we mostly just read when we aren't outside, because there is no space for projects. Skills and projects require tools, and a place to use and store them.
Food preservation and storage take equipment and space. Even if you sun-dry your produce rather than, say, canning it, you'll need racks, and rodent-proof storage and lots of it. I'm not saying you need the kind of big house that has become the norm--you don't., But I do know from
experience that a homesteader needs more space than an urban tiny-home dweller does.
You also need to plan for more space as you age, because of mobility issues and the equipment needs that age might bring. At 45, I slept on the floor and folded my bed up in the morning. 72, I prefer a bed, and not to climb a ladder to it. I don't want to have to move if I need a walker or a wheelchair, so there need to be clear spaces.
So yes, keep it small and simple. But plan for all the things you will need to do, want to do, and may have to do.