Teaparker reports that there is a renewed interest for artistic ware in Taiwan. Such pots take various shapes (wood log, bamboo, dragons...) or feature insects (snails) or animals (frogs) on them. For these teapots, form and aesthetics are more important than the function of brewing tea. So he calls them pots.
A teapot, on the other hand, will emphasize function over form. All its details will complement each other to brew a certain type of tea or they will seek a balance to be an all-round teapot.
This doesn't mean that you can't make tea in an artist's pot, but it's not likely to yield a perfect cup and it will cost you much more.
This also doesn't mean that functional teapots are not beautiful. We even tend to think that those simple lines and round curves are among the nicest objects to have landed in our hands...