I didn’t say this, I said that knowing there are “lower level” potential security issues I have to accept the risk
And this doesn’t depend only on source code availability (I remember some months ago the echo on the bug on OpenSSL which was present for many years although its source code is available since ever) so unless everyone is not able to investigate as deep as possible on every part of the device, we have to accept the risk of data leaking.
Why? If you know your phone might be insecure can you trust it?
Furthermore nowadays it is not simply a matter of your phone because with so many apps which leaks all kind of data, also your friends’ devices might pose a risk on your data. Some months ago for example I received an SMS from my mother and the text was an advertisement of Whatsapp, something like “Install Whatsapp to be able to talk with your friends” and so on (with also the URL to the Whatsapp website), but my mother NEVER sent me this SMS as she’s unable to write in English nor write an URL, BUT she has Whatsapp installed and I’m sure her contacts list was sent to their servers…Now I can’t imagine how many companies have my phone number even if I didn’t give it to anyone…
I fear we’re a bit OT so we can continue this interesting discussion in another thread if you like 
Bye!