Instead of digging your heels, and telling her your speech will be much more beneficial to both the students and the company, you did the typical nerdy thing and avoided confrontation and just left
I think OP did the smart decision.
You’ll never know if you don’t ask, and there are no stupid questions.
It's like when you learn a new language, one of the first things you learn is how to say "I don't speak X well, please slow down" in that language. Same with debate: learn how to say "I'm trying to better understand" to prime the other person for a conversation. Sometimes they'll start talking for you–that's even a common negotiation tactic, to let the other person talk to basically give you a few points to think about questioning/rebutting, or look for contradictions.
I think I'd only be able to do that if I'd had the same conversation previously. Come to think of it, sounds like just about every tech interview I've ever had.
It took years until I came around to the same realization for myself. It's significantly harder to coordinate and architect "layer 8" bullshit than it is to write apps or lay networks. And there's infinite layers of complexity in it as well.
You don't hear a whole lot of people in management claiming it's fun like you do in software engineering. That is probably a clue. Well, it was for me anyways.
This really struck home for me about 15 or so years ago. I was a "principal architect" at Travelocity, which meant that I was involved in driving the most complex technical decisions of the site. I felt like I was really doing well for myself - it was the top of the "tech track" there. One day, corporate asked people who had graduated from a set of local universities to speak to graduates of those universities - since I had graduated from one, I told them I'd be interested. The woman I talked to actually seemed shocked and said (no exaggeration), "Oh, I'm sorry, I should have been more clear, we were looking for people further along in their careers".