Pine phone Junior, message phone ?

[nelstomlinson]

Doing VoLTE calls and SMS/MMS and doesn't spy at the same time is literally impossible.
You will need to cut out the ISP somehow to stop the spying in this case, which you need in order to make calls and send SMS to begin with.
Even if you somehow manage to do so, you'd still need to somehow get around government-owned cell towers.

Doesn't spy was stating the case way too strongly. As you say, merely using the cell towers means giving away your location at the least.

VoLTE will apparently be the only way to use the cell towers at some time in the future. It would be nice to use the cell towers without using Google or Apple.

Digital communications are inherently insecure, and broadcast communications are inherently insecure, but it would be nice to cut the commercial spies out of the loop.