This is how ZigBee and Zwave work. The devices form their own network for inter-device communication (it can be setup so a switch talks directly to a bulb, so e

This is how ZigBee and Zwave work. The devices form their own network for inter-device communication (it can be setup so a switch talks directly to a bulb, so even if the network is unreachable it still works) and then you use a hub to orchestrate that and provide functionality such as phone control via an app. That can be something simple like a Philips Hue hub, or something more complex like SmartThings, or you can roll your own using Home Assistant and a dongle. The problem with these protocols is although they are more or less open, device manufacturers need to pay to be certified.