Earlier quoted context omitted.
this is actually the problem we have solved (for epaper). Compare https://www.youtube.com/watch?v=AKmfyThA9Sg to https://youtu.be/34I27KPZM6g?t=52
While you have certainly made huge and impressive improvements, I still don't think I could call that "solved". I think any latency is still going to put people off when it comes to writing on this vs. paper.
so we solved our goal, but it's always possible to get better.