That's my reading of it too. When pitching your product, these types of seemingly ignorant questions should be exactly what you're prepared for. Responding with incredulity is a terrible way to win people over.
It seemed to me that the questions (Eclipse? really?) betrayed not just a lack of familiarity or ignorance, but a deep confusion as to technology in general. That question alone made me laugh, as if the person was raising their hand and saying, "I have no idea what I'm doing."
I might possibly await that kind of response if they were pitching people with little-to-no technical background, but from YC I would have expected questions which, if not insightful, were at least moderately appropriate.
From the few minutes I've spent looking at Creo, there were a lot of valid questions to be asked here, but from what I read, none of those were asked. They flew a long way to find out that YC wasn't what they thought it was.
Actually I think the question about Eclipse was an opportunity being handed to them on a plate - rather than reacting defensively they should have explained the downsides of existing development tools and why their approach is so much better.
My reading of it was that the HN interviewer was trying to give them opportunities to explain themselves whereas the answers were defensive and impatient.
My reading of it was that the YC interviewer was so lost that they didn't know what question to ask. Of course, you're right, they could have corrected them and taken the opportunity to clarify further, but the question itself betrays a lack of any idea of what they should be asking. If I were Creo, I would also be (rightly) frustrated.
I don't see any reason to believe the YC side were playing n-dimensional startup chess here.
Occam's razor suggests they simply didn't read the info, and were asking dumb shoot-from-the-hip technical questions.
Having said that, the 'Do you have any users and have you actually built an app with this?' questions were entirely apt, and Team Creo should have had better answers.
Basically the product is nowhere close to being developed enough for a funding round. It has potential, maybe, but so far it's a programming exercise, not a potential business.
The experience highlights the continuing mismatch between developer expectations and funder expectations.
1. Write lots of code
2. I have no idea what happens here
3. PROFIT!
If you haven't thought seriously about step 2 you're going to have a hard time with funding - or even just turning your code into a viable business.