Here's what worked for me. YMMV.
- Turn off bluetooth so you can control your phone.
- Settings > General > Reset > Reset Network Settings to get rid of the message coming back.
- Turn bluetooth back on.
- For me, from here my phone stopped being able to receive network data (successfully connected to both 5G and LTE networks, but no data coming in or going out).
- Uninstall (and later reinstall) any VPN you have enabled. Not 100% sure how much this impacted things but my advice is to try this before moving to the next step.
- Settings > General > Reset > Reset All Settings
And boom... fixed. Everything working normally. The good part? I was able to avoid Erase All Content and Settings and a full restore. The bad part? This is still a PITA and you have to reconfigure everything after Reset All Settings.
I hope this helps anyone who is encountering this super frustrating issue!