Personally, having that much control from a keyboard doesn't interest me in the least. I posted the video because I thought it would be of interest to synthesists who are always looking for extreme expressiveness. But I find the keyboard to be already sufficiently expressive, when played well. It's expressive in its own way - not in an overly emotional, maudlin, or sentimental way with many nuances, but in a more dignified and noble way.
I, too, would have been more interested in the synthesizer.
This seems to be a recurring theme (extreme expression control)–but it's not dissimilar to that old chestnut, the battle between classical/liturgical and theatre/ballpark organists for the design of a modern organ console.
Theatre & ballpark organists, whose remit is to entertain, often make use of extra kick switches, roller pedals and momentary button tabs for triggering sound effects, unusual voicing changes, or drum / percussion hits. Classical & liturgical players, on the other hand, have no use for such things, and consider them to be abominations, if not simply gimmicks–yet they ultimately do end up on home organ designs, along with rhythm boxes, auto-accompaniment, etc.
But it's not unusual these days to find pressure-sensitive drum pads on a MIDI controller keyboard.
In fact–the same argument has been made against the organ crescendo roller pedal (which adds additional stops / voices as it is depressed)–yet you'd be at a loss to find a modern pipe organ for which the crescendo pedal has been omitted.
In this respect, every feature reaches a threshold of acceptance beyond which its inclusion is considered a must-have, as might be considered the case with MIDI controllers and (attack) velocity functionality. (Of course, Roland has been keen to omit aftertouch on many of its products as of late, including the JD-XA;
release velocity has never really caught on.)
So it might be the case that the sheer number of expression features within the Syntonovo prototype shown at Superbooth 2017 might have turned some people away, either by fear or on principle, though it is fair to ask: how many people would be as interested in the synth itself without the presence of an expressive controller to drive the synthesizer sound-generation engine during the demo clips?
Poly-AT is another case of this: few controllers / complete synthesizers currently on the market implement this feature, but it continues to re-emerge as a desired feature, and now as a component of MPE control...it may simply be the case that this particular Syntonovo prototype is ahead of its time....