Brax3 - a privacy-centric phone? Maybe not.

I have a need for a cell phone and am considering the BraX3 which is advertised as an open-source (it isn't fully open source), privacy-first smartphone. I wrote about it in my post, Brax3 - a privacy-centric phone by Rob Braxman.

At this time I DO NOT RECOMMEND PURCHASING THIS PHONE. I have sent multiple queries to Brax Technologies (support@braxtech.net) asking whether the baseband OS/cellular modem is properly isolated from the user-facing OS and memory. Their initial response was to refer me to a technical document, Mediatek Trusted Execution Environment (M-TEE) hypervisor isolation platform security target, which i can't make heads or tails of, thus i don't know whether it holds the answer to my question. Subsequent queries to Brax Technologies have so far gone unanswered.

Unless the cellular modem is properly isolated from the user OS and memory, it is my understanding that the BraX3 cannot possibly be considered to be a privacy respecting device.

Emails from Brax Technologies include the line, "Experience transparency. Like never before.". We'll see.