> If you have a bunch of Zigbee devices, but at some point want to add some of the new ones, you need to start thinking about replacing all the perfectly working Zigbee devices or have a fragmented network.
Yes, if you're using the manufacturer's half-assed smartphone app, but if you're on Home Assistant, like basically anyone who's serious about their smart home, having multiple kinds of smart devices isn't really a problem. It's just one more radio to configure. Some people run both Zigbee and Zwave, some people run Zigbee + Wi-Fi or even Zigbee + Zwave + Wi-Fi + cloud integrations, Home Assistant doesn't care.
Yes, if you're using the manufacturer's half-assed smartphone app, but if you're on Home Assistant, like basically anyone who's serious about their smart home, having multiple kinds of smart devices isn't really a problem. It's just one more radio to configure. Some people run both Zigbee and Zwave, some people run Zigbee + Wi-Fi or even Zigbee + Zwave + Wi-Fi + cloud integrations, Home Assistant doesn't care.