And it has an encrypted pairing process to your vendor controlled hub. Said vendor can allow or disallow it which other vendors may speak with said hub.
Here is the landscape we have: HomeKit: fully closed, requires certification from Apple. Very expensive and limited functionality.
Zigbee: fully open, anyone can make Zigbee devices and sell them without any restriction. Operates on the same frequency all over the world. Devices are super cheap. You can expand the protocol however you like as a vendor.
Z-wave: fully closed, several incompatible frequencies, requires certification to sell devices.
Thread and matter: semi closed, same ieee standard as Zigbee for data transfer. Vendors can allow it to talk to devices of other vendors. Requires certification. Same price tag as HomeKit, aka 3-4 more expensive than Zigbee.
All of them require hubs. And only with Zigbee you are guaranteed to have interop between all vendors and all devices sold across the globe. Thanks to Home Assistant. With thread the vendor can simply disallow you to use your devices with HomeAssistant, which is unacceptable by me.