Better late than never, I have 3 of their bulbs in the house, and not being able to integrate with HA prevented me from buying more (at least before Matter was announced). I've been using them with Google Home, so the lights weren't automated with HA. I'll try the integration out.
I have bulbs from wiz, which already have HA support.
Being new to all this home automation stuff I was quite intrigued how they worked though. They're exposed on the WiFi network over a really simple UDP based protocol which led me down a rabbit hole of writing a little go client to mess about with them, took a few evenings.
Not saying Xiaomi bulbs would be quite as simple to write an integration for, but they might have been. It's kind of fun seeing how people have reverse engineered all these custom protocols.