I just caught up on the thread, and it’s limited to Google/Nest devices (not including the Nest Protect). So, I don’t think there’s an avenue to share devices from Google Home to openHAB, as is the case with Alexa.
I’m actually tempted to get an Echo Flex just to mess around with this. Is there noticeable lag when you control your bulbs? I know that the reporting to openHAB is slow due to the 10-minute polling period, but that doesn’t really matter if you just want to send commands to devices.
I assume that it has to go through Amazon’s cloud, but that’s no worse than going through Tuya’s cloud.