Matter use Thread while Zigbee devices are not. How it will be co-existing and inter operable? In future, MATTER will replace existing Zigbee devices?

[Roman LUDIN]

Zigbee will not disappera from the scene at all . Zigbee is a very mature stack that's provide many advantages. CSA defines for Matter protocol the posisbility to BRIDGE to other protocols. On the market you will find soon bridges between matter and Zigbee for instance. In ST we already have this SW ready for testing. Get it from github Hot-Spot : https://github.com/STM32-Hotspot