I helped a friend of mine with her OS X laptop. She had installed something bad and it installed MITM proxy and its own CA and other things to totally own and inspect all of her web browser traffic including SSL. So these features that we find powerful and informative also do have a dark side for more novice users.
OK, but if it's a real security risk why do they only protect their own services? Why not have the user jump through a bunch of complex hoops like editing a plist file from an elevated terminal account? Hell, this is the os that makes it onerous to install software that didn't come from the App store. Clearly they don't mind throwing some user pain in front of basic activities.
