z-wave was proprietary which did not help its deployments, but still I recall it was the most deployed low power wireless devices for IoT. I worked on zigbee and never liked it. I wish z-wave was more open back in time.
Did not track what's going on these days for low power mid-range wireless, general feeling is that zigbee did not take off, zwave is used as before(you license it and put it to your sensors), and more and more are using low-power wifi and even bluetooth instead.
I can't really even find z-wave bulbs right now. And basically any device I might want (curtains, alarms, sensors, lights, motors, thermostats, etc) comes in a zigbee form.
I agree that Z-Wave did the better standards enforcement, but Zigbee went with the age old route to success: manage to be cheaper.
Throw in that the two most common automation situations tend to be either:
1. Upstream cloud service
2. Local management engine (ex: HomeAssistant, OpenHab, etc)
And it just doesn't really matter all that much how compatible devices are in terms of point to point control. I can just route the message through HA and take the action I want - mixing and matching as needed.
Plus - Alexa pro ships a directly integrated zigbee hub now, which got a lot of devices moving that direction, and Ikea makes some great super cheap zigbee devices.
Bluetooth and Wifi devices are the worst of both worlds, in my opinion. Wifi usually needs integration with an upstream service which is a non-starter for me, and bluetooth is just really limited on total device count. Both also eat through a lot of power compared to z-wave/zigbee.
It's pretty cool that several recent zigbee switches are completely battery/wire free. They literally use the energy you expend to push to the button to send the signal.
Even though you can find a Z-Wave bulb, it defeats the purpose of Z-Wave. Z-Wave isn't for consumables like bulbs, it works best for hard-wiring electrical devices into your home that will be permanently installed in a professional installation. I wouldn't feel comfortable putting a Zigbee switch in the wall since it's likely to become obsolete, whereas I'd be confident Z-Wave will still be around and supported in 10 or 15 years.
Zwave is still strong in the commercial space
ZigBee is strong in the consumer space, especially light bulbs that commercial systems do not want to use.
I'm thinking it'll be longer before zwave dies for real vs zigbee, but it will only live on the back of the big slow commercial entities that back it.
Hue has always been all-in on Zigbee. (incl the new 3.0 standard - https://developers.meethue.com/zigbee-3-0-support-in-hue-eco...)
Ikea has gone basically all-in on Zigbee (https://www.wired.co.uk/article/ikea-smart-home-kit-reviewed...)
Amazon is embedding it their devices (At least 4 different models include a zigbee hub: https://developer.amazon.com/en-US/docs/alexa/smarthome/zigb...)
Wifi is basically a non-starter for any real automation since it takes a boat load of power, and requires a non-local server (at least without some serious work on your part). It's a great intro spot for consumers who want to try a color changing bulb they can control with their phone, since the initial buy in cost is lower with no hub - but it's not really the same.
For z-wave on the other hand... I literally cannot find a place to buy a-19 standard socket bulbs that support it right now. Lots of "controller kits" but no bulbs.
Same for thermostats - there's like 3 z-wave thermostats on amazon right now. There are dozens of zigbee models.
Honestly - on Amazon at least, a lot of searches for "z-wave [device]" end up returning mostly zigbee results.
Ex: Go search Amazon for "Z-wave plug": Row 3 starts to return zigbee devices.
Go search again for "Zigbee plug": It's zigbee devices all the way down the page (one early result does both zigbee and z-wave, but otherwise you have scroll waaay down to see any overlap)
Basically - Having both Ikea and Amazon go in on Zigbee has radically shifted the market from where it was 3 years ago (when I would have probably agreed that z-wave was the better pick).
Philips Hue was always the big "Zigbee? Never heard of that" Zigbee producer, nowadays, there are also good and cost-effective things from Sonoff and Aqara, and cheap but hit-or-miss devices by tuya (heavily white labeled)
Z-Wave's primary advantage is, ironically, the openness of the ecosystem. Due to the lack of a stringent certification process Zigbee vendors can (and routinely do) lock devices to their proprietary hub. I'm guessing that is one main motivator for its failure. Though, keep in mind that Hue (one of the most successful IoT vendors) is all open Zigbee.
Zigbee's main advantage is that it's cheap.
Thread (the new standard to fix the old standards) is apparently just "Zigbee, the good parts". We will see if vendors drive it into uselessness like before.
That was a bigger deal when controllers were stand-alone electronics products, though. Being in the cloud, a controller like SmartThings can add one-off support for non-standard end devices at any time, so there's less need for everything to be on one standard.
zwave by default is at 900Mhz so it goes much further than 2.4Ghz and it even has a long-range version(for a few km), that's another advantage of zwave.
all of them are low-power, all of them need a gateway or hub to talk to wifi and the internet, other than zwave is strictly co-operatable, zwave is also *much much* simpler, if zwave truly opens up, it could take over the competitors IMO.
I haven't had much luck with Bluetooth and Wifi IoT devices. They tend to last a couple of years and then die. They also are more hassle to set up, and use more power. I don't need more hassle in my life. Z-wave and Zigbee are both more reliable, with Z-wave taking the slight edge over Zigbee.
What's happening now is Thread (Matter) is coming. Thread is basically Zigbee Mark II. Thread is on par with Z-wave, but it supposed will retain its edge in cost benefit. I may start buying Thread stuff as it becomes available, but the problem is my mesh is solidly Z-wave. It doesn't seem worthwhile to start replacing stuff that works perfectly fine.
Home assistant docs because I can't find a better description: https://www.home-assistant.io/integrations/zha/#binding-and-...
I've fallen back to physical switches that can be relay controlled.
