It wasn't selling points though, it was specific rebuttals to specific things that someone had said about his company in public.
It should cut both ways. If you want to publicly say "hey this is what I think of company X," people with company X should be able to say "hey what you said is bullshit, and now that you started the conversation I'm going to explain why, whether or not you feel like the conversation needs to continue after your side and only your side has been expressed." I mean, the CEO was way more polite about it than that for understandable reasons, but I think some level of that frustration is probably behind him wanting to be able to explain himself even after she said she wasn't interested.
Such is my opinion at least. As long as nobody's getting sued or silenced or harassed at length beyond a few emails, he who opens the slinging of ideas that aren't friendly, should be prepared for responses to their ideas to come back at them that might not be friendly. This whole "free speech for me but then shut the fuck up and don't tell me anything back about what I said" seems unfair. At least, in my opinion.