So I figured out how to enable OK Google after hitting the Google App Icon. Kind of.
First a recap; I had turned off all Google App Permissions and disabled it. To completely disable OK Google I had to remove the OK Google Widget that was installed one year ago. I had been using the widget and enabled it only on one screen. Sometime this Summer an update enabled OK Google from every home screen, and even enabled it with the screen off. Disabling OK Google using Google, Settings, Voice, "Say OK Google any time" OFF, did not disable it until I deleted the widget from my home screen. Apparently the widget over-rode the settings. In addition sometime this Summer my vehicle, (a 2016 Chevy Express Passenger Van), no longer called out through my phone. Hence this thread.
Now once turning off all Google permissions and turning off voice, Only enabling Google, Voice, OK Google Detection, While Driving ON. My vehicle would not use voice dialing to call out using my phone. When I hit the call button, the say "Voice" to the GM Vehicle, the phone would light up and tell me I needed to enable OK Google, or OK Google did not have the needed permissions.
I also found that hitting the Google app button, came back with I must enable OK Google permisions. Specifically open Google, Settings, Accounts and Privacy, Google Activity Controls, then enable Web & App Activity, Device Information, Voice and Audio Activity, and Google Location History. Why I need all these enabled for OK Google to work at all is beyond me. Why they might be needed to call out from the car is also a mystery. Controls are only useful if you really have a choice.
Now hitting Google, allows OK Google to work on the phone. But from the car, when I hit the call button, the car comes back with Ready, I say "Voice", and the car connects to the phone. The phone lights up. I hear the prompt through the car, Then I say "Call Laurel on Mobile", and the phone says "Calling Laurel on Mobile using Speaker" through the car. Then the car connection is closed and the phone call continues using the Phone speaker and microphone. I'm getting closer, but I want the phone to stay on the bluetooth connection and not switch over to the speaker when I initiate the phone call through the bluetooth connection. I can hit the bluetooth button on the phone app call screen and reconnect to the car. But again, that is no longer "Hands Free" plus it requires that I take the phone out of my pocket before I get into the vehicle.
Hopefully someone might be able to tell me the hidden secret new command to tell OK Google to "Call Laurel on Mobile", maybe "Using Bluetooth?" Software updates the change the way the phone works by adding new features that no one knows about are not useful. Just frustrating. Like the first time I encountered a tiny tiny carrot that looked like a funny period at the end of the page and could not follow instructions online as the screen I was looking at did not look like the one on the web. Not to mention that someday we won't be able to see anything that small.
Once again I wish Google tried their stuff on us old folks. The joke will be on them when they grow up. Then maybe they'll get it. Imagine if they used their great search engine to figure out that old people do not spend their money because they are not making anything that old people can actually figure out how to use. (I am a retired Kodak Research Scientist who has built numerous machines that were too complicated for anyone to use. Even the people who hired me to build said complicated equipment.)