This is exactly what I came here to say. On top of that I'm not sure how the data from the second chart got put together? It just says that the data came from their own site and IDC. IDC's report for the 3rd quarter puts three competitors above Apple in terms of market share, YOY growth, and unit sales.[1]
1) Garmin is selling almost 20% more than Apple
2) Fitness is the killer app for wrist-wearables. The 3 front runners are fitness focused.
Problem with Xiaomi have been more supply side than demand side. I know because I tried to buy MiBand 2 when it originally came out and for weeks most vendors were sold out. It's possible that Xiaomi is having trouble keeping up the manufacturing volumes at the low price point they've entered the market.