It's not completely irrelevant. Having "security issues" is bad news for market share. The question wasn't asked in an isolated context - it was in the context of "bad news for market share". That's exactly why Lazaridis got emotional about it.
Mike's point was there are no security issues with the Blackberry. The issue is that there's too much security than what some governments can tolerate. The question puts the CEO right into a paradox that nobody can possibly answer, so it was fair for him to end the interview (or maybe he could say, a lot of this is under negotiation so he can discuss it).
He can't be critical of the governments demands because they are in negotiations with them. He can't say they will weaken security, because that's not what enterprises want.
Either way, you have to be proud of a company for taking a stand and developing secure products that could help protect civilians from terrible governments.
