I think - at least for the people who stick with a career in PR - that they enjoy playing the game of giving an answer that is sort of related to the question but doesn't actually give a single bit of useful information. That they enjoy seeing how far they can push it without the interviewer straight up accuse them of not answering the question.
At least that's the only way I can imagine them keeping their sanity.
Is that really a concern for most people? Trying to keep hostnames secret is a losing battle anyways these days.
You should probably be using a trusted TLS certificate for your git hosting. And that means the host name will end up in certificate transparency logs which are even easier to scrape than DNS queries.
At least that's the only way I can imagine them keeping their sanity.