[Lendal]

The new Thread protocol (part of Matter) is basically Zigbee on steroids which gets it up to parity with Z-wave. The reason to choose Z-wave over Thread is that Z-wave works now and has many devices available to buy, while Thread works in theory and the devices are very few in number. Thread devices are due out in force next year. So this actually is perfect timing for Z-wave to make this move now, right as the first wave of Thread devices are approaching.

[xattt]

There were a bunch of missed opportunities for Zigbee to become enshrined in the home.

For example, the first and second-gen Nest thermostats had a Zigbee radio built-in. At acquisition by Google, Nest heavily leaned into the wifi/cloud side for control and the Zigbee radio was squandered, other than for some esoteric “Works with Nest” protocol that maybe 2 other third-party devices supported.

Edit: I stand corrected by the comment below.

[oflannabhra]

That is an inaccurate history. Nest has always been IP-based and drove much of the initial Thread standard. Their radio was 802.15.4, but not Zigbee.

[solarkraft]

> Zigbee on steroids

It's definitely not as proprietary, which is probably relevant to a lot of potential implementers. There's close to no public information about Zigbee implementations while Google invites people to implement Thread through OpenThread.

Thread likely has more features with some pretty fully featured networking support, which some may consider positive, but some negative.