then we are arguing different things. i'm not exactly saying having the source code is the only way to assure a device is private. i'm arguing an US company known to take part in the PRISM program and involved in the currently openly fascist admin using the surveillance to hunt people cannot be trusted at all. i can sound oppositional sometimes but i'm not arguing in bad faith at all.
also "reading the source code" is something done in community, not individually. this is a very important distinction. i don't know the linux kernel is safe because it goes right over my head, but there are plenty of well intentioned eyes on it that do in our community.
iphone hardening is to me like installing proprietary antivirus software on windows. you are not any safer at all, and the impression of safety and the dropping of our guards that it causes is detrimental for real safety. we shouldn't be wasting time thinking about ineffective half measures, we should want to be safe.