I disagree. Microsoft has 13,5" and even 15" 2-in-1 Windows 10 tablets, and both are best sellers:
As a matter of fact, they’re even high-end products, and despite their size and price, they keep selling. Why ? Because they’re powerful enough to replace a professional laptop, with a screen big enough to work with comfortably (not with a ridiculous 10" to 12" screen), and with a rigid chiclet keyboard, not a soft plastic one.
Maybe Chuwi should rethink WHY Hi13 and CoreBook weren’t best sellers. It wasn’t because of the size or the weight. It was because of their inability to replace a professional laptop. It was a marketing mistake because of their specs, not because of their size. They were aiming the wrong market, that’s all.
For example I could have bought a CoreBook, but having only a 128 GB (non-replaceable) SSD was a deal-breaker for me. I even wrote to Chuwi to tell them about it, but they never considered offering more expensive alternatives (256, 512…). Too bad. It would have been so easy !
Now IF Chuwi can propose a real laptop alternative, with real up-to-date laptop specs (i3/i5/i7 or Ryzen CPU / 8 GB RAM / Up to 1 TB SSD), with a real keyboard and with a detachable tablet part, THEN it will be a success. 
Actually that’s all we’re hoping for : not just a big tablet, but rather a regular-sized laptop with a detachable tactile screen (and I mean “detachable”, not just with a 360° hinge). Is that too much to ask ? Microsoft has been doing it for several years now. And we’re still hoping for a chinese Surface Book alternative with a 13,5" to 15" screen. Why ?..
Thanks.