> The resources dedicated to securing non-free software may be far greater than those dedicated to free software because of the business interests in maintaining security.
My argument is about confidence---you cannot trust a system that you do not have confidence in.
Yes, a proprietary system may have had much more development and research. But that doesn't make it "better". With a free system---even if it's more poorly designed---you gain confidence in being able to observe _exactly_ what it does, faults and all. You know what to expect, and what not to; that's far more important than not knowing either of those.
Further, the general recommendation among cryptographers and security experts is to use public algorithms that have been torn apart by cryptanalysts for years---all security should be in the key, for example, _not_ secrets in the implementation.
> Google has done a lot to improve the security of a variety of open source projects, but only because they form part of a non-free core that would otherwise be compromised. The same holds true for Apple albeit to a lesser extent.
This is security through obscurity, and is antithetical to actual security.
> A free system can much more easily be compromised by the injection of cloaked vulnerabilities by actors such as the NSA.
I don't follow. This is one of those situations where you _always_ have more transparency in a free system than a proprietary one---you are able to see _every_ patch that makes it into the system. That doesn't mean that you'll catch everything, but you have the opportunity to do so. And not just you---everyone.
> You actually haven't shown anything. You have simply stated that transparency trumps everything else. This is false. Transparency simply diffuses the trust model.
You cannot have confidence in an opaque system.
> More importantly, as I keep saying, nobody has ever produced a transparent system that can be substituted for Apple's system. Until they do, these arguments that a theoretical alternative would be better are imaginary. If it was as simple as you suggest, why hasn't it been done, or at least demonstrated?
Which system, in particular?
Apple's system should not be used and cannot be trusted---it is proprietary and designed to control the user in countless ways. Apple may take measures to protect their users' privacy and data, but ultimately, users are at Apple's mercy, and Apple has the final say in everything. Apple is historically one of the most opaque, secretive tech companies in existence.
So any free system is an improvement over Apple's.