This article seems to only talk about the ones that fold like a book, and not on the ones that fold like a clam. I don't get the fixtation on that design - at this point it's more of a tablet than a phone, and for a tablet it's pretty small. When opened, the Samsung Z Flip has the dimensions of a smartphone - which means you can put it to your ear or operate it with one hand. You can't do that with the Z Fold - it's too wide. Also, the Samsung Z Flip costs half as much as the Z Fold - which is still not cheap, but it's not that much more expensive than Samsung's regular flagship phone with the same specs. So I assume affordable flip smartphones should be possible - maybe not this year, but probably soon enough.
Z Flips sell twice as much as Z Folds - all while Samsung is spending most of the marketing effort on pushing the Fold. Maybe if they focused on the Flip instead they could have made this one "a thing"?
The tablet thing is the point I like about my foldable phone. I couldn't be bothered to carry a tablet with me, but the Fold fits in my pocket without any issues and I love the bigger screen.
If I have to use my phone with one hand, I just use the outside screen (which to be fair hasn't the best aspect ratio).