I have an old stand, in perfect shape, that I improved over time.

It is too heavy for some, like those out of shape or have a bad back.
It is big enough for me; too small for a 270 lb. hunter. The seat fits my backside, but surely not everyone.
My stand has a rail of some type; isn't a open seat. Some of us are prone not to like "open diving boards" and like the constant reminder that we're 20-25 feet off the ground.

I have a back on the stand, where I don't have to prop my back up to a tree for hours. I can face the tree, and use one tree as cover, if all the leaves have fallen.

So the most popular stands aren't necessarily for everyone. And I hope they never come to one size fits all. Because that tree stand never existed, in my opinion.