Hmmm
I can see your point, but I'm not sure I agree. That's not to say you're wrong, I'm not arguing that.
I see it more this way. Apple spends the effort necessary to make it very difficult for the average user to leave the confines of iOS. At this level Apple is absolutely dedicated to making sure the average user can't break out. They also spend a considerable amount of time putting the word out about how bad and wrong and evil it is.
Piracy, voided warranty, unstable, insecure, etc. And the typical Apple fanboy you can find on Apple's forums helps Apple spread the bad word. This stops everyone except the dedicated user. Those Apple can't really do much about because they either know more than the average user or are willing to learn. The effort to stop those users isn't worth the investment. So, Apple makes a best effort and then moves on. In some cases it lets the jailbreakers find out their security holes for them. In that way, I could see your theory having merit.
In short, I think Apple is highly dedicated to stopping the common user, but recognizes that there is not much they can do to stop the determined user who is hell bent on breaking out.
Just my take. Again, not saying you're wrong.
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Yep. It comes down to control. Apple wants to control your experience and is unwilling to cede that control to you.
In some ways, especially in light of the same old inane, moronic and repeated questions on the JB forum, I have to agree with Apple.
Some people should not be allowed to jailbreak.