Ya basically Bixby disables the camera voice control feature. You can open your camera app and say 'Hey Bixby take a picture' . That works. A bit more wordy the just saying 'smile'.
Youre speaking to it wrong. Either that or bixby causing problems. There are a lot of people with threads about Google not working and bixby seemed to be the culprit.
I don't have any of these issues mentioned here. I just used Google Assistant to launch the camera and then used voice control to take about 5 pictures using different trigger words. Hopefully you guys can get your kinks ironed out. Bixby has been a pleasant surprise thus far.
I can confirm that having Bixby set to always listening disables voice control of the camera. Turn off that option in Bixby's settings to regain the ability.
Very frustrating... I would think after all this time it would be resolved! I would like to try and like Bixby but my camera voice action is used multiple times a day