Obscurity and secrecy seem to be so ingrained in the Apple culture that I don't see this changing anytime soon short of some kind of existential crisis or a major threat to a substantial amount of their revenue. And even then it isn't likely to be easy to turn the tide.

Right now we see these negative externalities of security vulnerabilities being "paid for" by their customers, in the vast majority of cases seemingly unwittingly, but that can only go on for so long before it backfires (even if it's a long time).