[General Questions and Answers] GalaxyA325G:
Thank you for letting me know the solution will also be useful to you as that's why I asked it.

We want a definitive solution for people like you and me (we can't be the only ones who care about our home AP privacy).

I think anyone who is concerned about their home privacy wouldn't want their SSID/BSSID/GPS in a public database if they didn't expressly opt IN on purpose.

The default assumption by Google (and many others) is, I suspect, that if you publicly broadcast your SSID in the clear, then you're opting in.

Even though I disagree with this default assumption I have to understand the logic which is why I don't broadcast my SSID.

By not broadcasting my SSID I'm (hoping) it's signaling my intent to opt OUT.

I thank you for that idea of lowing the signal strength (which only some routers will allow, I think) but I need all the signal strength I can get.

And more to the point most people need all the signal strength they can get, I think.

Even so, while lowing the signal strength may help, it still won't work for the Android devices that walk close enough to your front door to access your signal after using Google Maps.

Pragmatically, all it takes is the postman or the Fedex guy or the UPS guy to have his Android phone on with his "Google Location Accuracy" turned on.

It's even worse if they have "Improve accuracy" turned on, as that adds additional "Wi-Fi scanning" and "Bluetooth scanning", which is another can of worms we'll stay out of for this thread.

Speaking of Google Maps, you can "fix" the problem of Google Maps secretly turning on "Google Location Accuracy" but you have to go into your Android settings to find the special Google Maps (Google Play Services actually) "activity" named

com.google.android.location.settings.GoogleLocationSettingsActivity​

Actually the activity Google Maps used is a secret undisclosed activity one step BELOW that com.google.android.location.settings.GoogleLocationSettingsActivity activity since the "OK" in Google Maps automatically secretly toggled it on.

Nonetheless, I set a shortcut to the com.google.android.location.settings.GoogleLocationSettingsActivity which allows me to turn the "Google Location Accuracy" toggle off (while leaving the "Location" toggle on) after I say "OK" to the Google Maps query to turn on location.

BTW, the undisclosed hidden secret activity is a specific Google activity that only Google does, as far as I know.

No other program that I know of secretly toggles "Google Location Accuracy" on other than Google Maps which is one reason Google is being sued in Arizona as we type for their secret tricks to get our private data uploaded to their public servers.

Here is where our little secret lies!

I have absolutely no doubt that the phone's radio picks up the hidden BSSID (because I can see the hidden BSSIDs on my phone when I use any decent Wi-Fi graphing app).

However........

It's my understanding (which I need to find a reliable source to back it up) that someone's phone that is typically set to upload the SSID/BSSID/GPS by default will NOT upload that BSSID if it's hidden.

What's important is that sentence assumes that the typical upload of the SSID/BSSID/GPS requires the SSID to be broadcast in the clear.

If that's true, then simply HIDING the SSID broadcast beacon will stop other phones from uploading your SSID/BSSID/GPS to not only Google servers, but potentially Mozilla, Kismet, Wigle, Netstumbler, and other servers.

Note that I'm not saying it can't be done by a determined program. What I'm saying is that it's my understanding that it isn't done.

Notice the profound implications?

If I'm correct, then HIDING THE SSID broadcast is far BETTER than using _nomap (although I'd still use nomap also) simply because hiding the beacon broadcast is making it clear your intent to even those public databases that do not respect the nomap.

I think this is the way the Android SSID/BSSID/GPS upload typically works.

Of course ... there's more to the story...

One problem with hiding your SSID is that it kicks the privacy can down the road because now your phone is constantly asking by name for that SSID when you're not connected and your Wi-Fi is on.

Of course, there's a simple fix for that secondary problem (which works in Android 11 at least), which is to set your Wi-Fi on your phone to stop asking for your hidden SSID when you're out of range of it.

That don't-ask-by-name-for-my-hidden SSID setting on Android 11 is

Settings > Connections > Wi-Fi > (select an SSID) > gearicon > Auto reconnect = OFF

I would like to find a reliable source that backs up that guess that Google and Mozilla and the others (Kismet, Netstumbler, Wigle, etc) "don't" get your SSID uploaded to their servers by default if your home AP SSID beacon broadcast is hidden.

Notice I said "don't" which I think may be the case only in the default situation, as I'm well aware any determined person "can" upload even your hidden home AP BSSID/GPS information manually to any public server they want to.

In the end, I have a solution that I'm constantly honing to improve it where I want to accomplish two things here.

I want others to be able to do what I can do, and

I want others who know more than I do add to what we can all do in terms of keeping our SSID/BSSID/GPS out of Google's hands (and that of Kismet and the rest).