I agree with this. I have a son with severe anxiety and he just had his first full blown panic attack last week. I have had panic attacks too, so I know what it feels like, but this happened in a doctor's office while he was undergoing allergy testing, so we all thought it was anaphalaxis! It was so scary for him...he turned red and flushed and broke out into a full body sweat and was hyperventilating. He is only 13 and autistic and it was hard to explain to him what was happening and help him get through it. He had to lay down for quite a long time to get through it.
If this happened to us at WDW, I would have used the emergency exit anyway and let the Disney management deal with me after the fact. And, if they even TRIED to tell me that we had done something wrong, I would have promptly called a lawyer. That is unacceptable.
Those emergency exit doors lead to the outside and are perfectly safe to use at ANYTIME during the show. That is why they say "if you need to leave the theater during the show, please alert a cast member."
I really hope the family of that gentleman went to guest services after that and complained. That could have totally ruined his entire day.