Re: How does incoming caller ID work - and more specifically - can caller ID source data be controlled?

UPDATE:

I updated my Moto G7 from Android 9 to Android 10, where I'd have to check
my screenshots from the past, but it seems in Android 10 there are two new
"Default apps" settings (that were not in Android 9).
o Those on Android 10... is it worth upgrading from 9 to 10? 
  What are the pitfalls you've experienced & the benefits?
<https://groups.google.com/forum/#!topic/comp.mobile.android/X65cMyzAn-g>

o Android 10 Settings > Apps & notifications > Default apps > 
1. Assist app -> Screenshot Assistant
2. Browser app -> Tor Browser
3. *Call redirecting app* -> None (I think this is new!)
4. *Caller ID & spam app* -> None (I think this is new!)
5. Home app -> Nova Launcher
6. Phone app -> Contacts (i.e., SimpleMobileContacts, not Google Contacts!)
7. SMS app -> Pulse

If others know, offhand, how to take advantage of these two new "defaults",
please let me know, as I'm testing out, for years, a phone that is
different from most Android phones in three privacy-aware ways:

A. I do not have a Google Account set up on the phone
   (where you can have a Google Account, but just not set up in the OS)

B. I replaced all Google apps which required a login or which phoned Google
   (most of which are very easily replaced with privacy-aware apps)

C. I do not have a default sqlite contacts database in the normal location 
   (because Google tends to upload that db without your knowledge)

The _only_ thing I was having trouble with was incoming caller ID for
contacts that are in my private contacts database, where maybe these two
new defaults in Android 10 can help solve that problem?

3. *Call redirecting app* -> None (I think this is new!)
4. *Caller ID & spam app* -> None (I think this is new!)