I read that statement less as arrogance and more as one's internal thought process when an interview starts to go in the wrong direction. Before any interview or presentation, I have an idea in my mind of how the conversation is going to go (some canned answers here and there for info that requires a concise explanation, some general ideas to touch on, etc.).

I'd guess that never in these dev's rehearsals did they imagine they'd be defending their validity as a product over a product like Eclipse.

That's not to say that the question was wrong to ask; in fact, I think it was one of the most important questions asked at that interview because it gives the Creo team great insight into how people are trying to "fit" their product into the current market. I do think, however, that the question threw the Creo team for a loop because it doesn't allow them to highlight the benefits of Creo in a meaningful way.