Oh dear. I'm sorry that I attracted your attention or confused the issue by mentioning a lot of unimportant details.
The point of my post was nothing to do with voice calling, origins of Android, Fibre Optic in Europe, or SMS 2FA.
Where did you learn/read that?
I learned it as the result of several conversations with Cox Communications officials: on the tech support line and in-store in person. That's the nature of the service as envisioned by Cox Communications.
Here's where we've got it backwards:
It doesn't count against your bandwidth if you allow it to use the hotspot(Coxwifi) instead. Also, internet traffic will go through the wifi. If you want it to go through cellular, turn off wifi on the phone.
But here's what I'm saying. Cox informed me that customers with Cox Mobile phones shouldn't be using their Panoramic Wifi while at home. The Cox Mobile service provides Mobile Data for us to use instead of WiFi, and it's metered and capped separately, and so to use Panoramic WiFi at home is "cheating" or "hiding" the actual data usage of the Android device.
In view of this restriction, I used the Panoramic WiFi app to "Pause" the Android/Cox Mobile device, so it won't be permitted to use Cox Home Internet bandwidth instead of its designated Mobile Data connection.
Panoramic WiFi, Home Internet connections are far faster and with far more capacity than the mobile network. At this time, it appears that the "Gig Unlimited" mobile plan offers 20GB per month before throttling bandwidth. Mine's using 6-8GB, if I'm out and about, using it freely. "Pay as You Gig" is a fixed cost per Gigabyte used each month, and throttled above 5 or so.
I have a second Android phone, which I'm using WiFi only, and I was mulling over a second "Cox Mobile line" and installing a SIM card, but this would degrade my service and cost more, so I will need to pretend it is a tablet and not a "phone" because I choose not to utilize the SIM card/Mobile Wireless option on it. Cox issued this Pixel to me, and it's natively running Android apps where I need them, especially in my pocket while not at home.
But a Mobile Wireless plan is the only sane way to access voice calling and SMS texting, and believe me, the 4G/LTE/5G service is the only way to go. My voice calls are crystal clear with great reception, and I use dozens of SMS per day for important tasks, quite reliably. You'd be surprised how many millennials communicate solely by SMS/RCS.
Mobile phones are mobile and used outside the home. Cox offers a telephone service for customers to use inside their homes, so there should be no need to use a Mobile Phone while sitting around the Home Internet/ Panoramic WiFi service area.
It's not a question of how I, Anesti33, want to communicate, but how my contacts choose to reach me, and how Cox Communications architects their services.