I see the potential of Bixby but the lack of Commands make it useless or poor. The following commands are needed.
1. Turn on Maximum Power Saving Mode. Bixby will go to the page. But it will activate or apply.
2. Switch off Mobile data . Bixby will go to the page. But it will not turn off or disable or switch off mobile data.
3. Switch on Airplane mode.
Solved! Go to Solution.
Bixby re-added the ability to turn on / off airplane mode in a ~ June 2019 update.
Note Bixby cannot function when the phone is offline so Wi-Fi must be enabled.
I setup phone to not turn off Wi-Fi when in airplane mode using steps similar to those here
"turn on/off mode" no longer works but "enable/disable airplane mode" still works and "enable airplane mode" and it would work.
I setup airplane mode to not disable WiFi. Then I'm able to continue using Bixby Voice (e.g. Quick Commands) after I have enabled airplane mode. IMO Samsung should make it simple for other people to make this change to airplane mode. I had to install Android Studio and run adb commands which most people will never do.