Ad hominem can be completely appropriate if you're making a point about someone's character/credibility. I don't know why people think that ad hominem means you should never make arguments "to the man."
In this case, I think he's saying that because these are politically motivated shareholders, a reasoned answer would be lost on them. Cook could have whipped out a lengthy powerpoint full of charts and figures, or he could have done the chicken dance, or whatever ... he's saying the shareholders are not asking the question in good faith.
edit - Further, saying what you would prefer Cook do if you had asked the question isn't entirely relevant, since presumably you would be asking sincerely. Cook can probably tell those guys are only there to yank his chain and make him look foolish, so unsurprisingly he was somewhat hostile in response.
1) You're obviously a troll with a 20 hour old account, so you feel like you need to get trolling early today.
2) You assume that people who disagree with you on some topic have "rejected science as a legitimate world view". You should try to reexamine this assumption, as you may find out it's invalid.
You can't "disagree" about climate change any more than you can "disagree" about heliocentrism. Also, notice that we can have a discussion despite the fact that you just threw out an ad hominem.
Hmmm, after much consideration, gonna go with ad hominem.