Read it again...this is enabled on ALL iphones. All I need you to do is plug your iPhone into my PC. Voila...I now own your iPhone (so to speak).
I suggest you re-read. This appears to be a flaw in iTunes, not iOS, where if the user is stupid enough to download an app from an unauthorized/untrusted site that knows how to do it, the app then exploited a feature in iTunes to make it a "trusted" source of apps and could proceed to download other apps without authorization.
That's not "owning" my phone, nor can your version of iTunes do that without you specifically targeting it. Worst case: you can install some crapware on my phone that I can simply delete. If I were idiotic enough to compromise my phone in the first place.