A raspberry pi4, Home Assistant software, a zigbee dongle, and any zigbee-compatible smart bulb.

By default, the traffic never leaves your local network, and all your smart-crap still works if the internet goes out. At one point, it had a learning curve like a brick wall, but over the last year or two, they've done a spectacular job of improving the user experience. it's still not perfect, but it's far better than the commercial alternatives and won't harvest your entire life for metadata it can sell.