This is the correct answer. The bulb itself doesn't necessarily have to be FOSS. Really you just need bulbs operating on something other than wifi, and ideally without a proprietary hub. Hue bulbs can be made to run on ZigBee. Z-Wave bulbs also exist. Then controlling them should happen through HA. If it's just LED strips, ESP controlled ones are a great option.
Ikea has pretty good "smart" bulbs. They use zibee, so you don't need their controller. You can use a raspberry pi with a usb zigbee antenna connected to it, and Home Assistant installed to give you all the features you would want, while keeping it 100% local.