And there are other good reasons why its not included, it's nothing about cost it's the same reason ST didn't want to put WiFi in their V3 hub but was pressurised to do it.
Now they have it they tell people not to use it.
ZigBee and WiFi are both 2.4ghz and they can cause interference with each other.
100% we can and the argument is signal.
I prefer wired, only because of my own personal experiences 
Out of personal interest the older hardware versions of Hubitat you had to plug in USB dongles is that right? Perhaps a Wifi dongle could be used? I could be wrong?
There is a gap in the market, I'm aware of that. There is no option in the market that has all the features I want.
For the people saying about interference between ZigBee and WiFi, this can be eliminated with carefull planning. It will happen anyways if you are using WiFi and ZigBee and they both share the same channel. But you pick up different channles for the WiFi and ZigBee, no interference will occur.
I was studying possible solutions to my case, and if I want to try Hubitat I'll have to buy another unit of Deco M9 to connect Hubitat.
The first time I read about the Hubitat I was very excited, because it works locally and has support for many different devices. To me the fact about the missing WiFi drops one "star" from my review, but it should not be an impediment to use it.
Respectfully, while this is technically true (to a point) it is somewhat misleading, as WiFi and Zigbee certainly can coexist in the same RF environment as you state. However this is different than coexisting on 1 PCB (or in 1 little 4 x 4 x1.5" box).
When you have a WiFi hotspot a few inches or feet away from the Zigbee radio, (e.g. your Deco M9) it is still much further away RF wise than when it is on the same PCB or within the same Hubitat box.
RF on PCB is hard. More radios = harder. Just because Zigbee and WiFi can exist in the same RF environment doesn't mean that its easy or cheap to put them on the same PCB. Nor does it mean that its a good idea. Their frequencies are very similar, and filtering out their local products so as to not interfere with each other is hard (=expensive), especially with multiple radios, all coexisting in each other's near field emission pattern. It can be done, and no doubt has, but it isn't the best solution.
Having said that, I get what you're aiming for, and it makes sense for your use case. It sounds like you have a solution, although I'd be reluctant to put the Deco M9 within a few inches of the Hubitat, it should work for what you want to do, if you do this, I'd suggest keeping a few feet between the two devices.
Best of Luck.
S,
Thanks for the information. I have played with PCB design and built some simple RF transmitters, I agree that designing RF circuit is challenging. So it has been an economic decision dropping WiFi for reducing the price of Hubitat, without compromising its major functionality.
I'll follow your suggestions.
Download the Hubitat app
