NetRunner88 Thanks for the clarifications. I'm aware of LLMs weaknesses, which is why I tried to run through the steps on my own before sharing. It definitely wasn't as concise or perfect for every situation, so I appreciate you clarifying some of those details. That was helpful.
I imagine any MVNO that uses AT&T's network would also need Carrier Services installed, right?
Thanks for mentioning adb. I've used it several times before, but not for this specific thing. I definitely prefer to use vetted tools rather than questionable third-party apps, so I'll keep this in mind for the future.
Why do you say you don't need to enable phone number verification in sandboxed Google Play? This seems to be the only change I made after the day I tried to enable RCS and it got stuck on the "verifying" step. Is there a way to manually verify your number?
What part of my configuration resulted in me "giving everything to Google"? Installing Play Services with network access? Enabling automatic number verification? Installing Google Messages with network access? I intentionally didn't sign in with my Google account anywhere on this account, even in the browser. But perhaps they can associate it with my account via my phone number, so I see your point. My understanding was that RCS from Android to Android was encrypted. I know it's not encrypted Android to iPhone yet though, so I imagine Google may have access to that.
Based on what you are saying, I'm thinking there's sadly no way to use RCS without handing revealing information over to Google. Is that accurate?
I'm still weaning myself off Google, so I haven't gotten to the point of fully cutting off my relationship with them yet. I'm soaking up what I can learn on this journey.