> Being "state of the art" means being the highest level of development or achievement in a particular field, device, procedure, or technique at a specific point in time. I don't think it's therefore unreasonable to expect supposed "state of the art" text-to-speech synthesis to do far better at everything old-school TTS could do and then some.

Non sequitur. Unless the 'art' in question is the 'art of adding features', usually this phrase is to describe the quality of a very specific development, these are often not even feature complete products.