The reason must be that the open source firmware can be used with more confidence and can be customised with some interesting features, for example, we use this thermo-hygrometer to turn it into a remote display that can be used to HA information about some interesting properties. And these can be used to allow us to study the protocol stack and familiarise ourselves with these Zigbee+BLE protocol chips made in China, which as a start will help us to start making some of our own low-power sensors, such as perhaps low-power radar sensors.
The other thing is that as a low-power sensor, we want it to be as stable as possible, personalised, able to be customised with, for example, the update rate that's needed, the update strategy that's needed, and these can lead to possibilities.
And finally, the other thing, maybe, is that some of these individual Zigbee sensors are expensive and may not be manufactured in the same high volume that these BLE sensors are. That could lead to a different kind of feature
I think where things get really interesting is that we can gather what people need and then gradually build on that hardware base and add some interesting and wonderful features, and that could be fun to do.
