I think that's about right. I don't want to give the impression of being simplistic about this; it's just that if HN is influential, the best way for that influence to function is if we neither focus directly on it nor try to exclude it, but leave it in peripheral vision.
There's a related issue, which is that the better HN gets at its core thing (curiosity), the more the audience grows in quantity and/or quality, and then the more people then want to use that audience for something else. Sometimes that's to promote their company or event, sometimes it's to bring attention to some other matter—maybe more important than what's actually on the front page here. The more those things become the focus, though, the worse HN becomes at the core thing, so there's a sort of paradox where the better it gets, the worse it gets.
What seems to work is to focus on the core but not too rigidly. This is a good because rigidity turns into predictability which is bad for curiosity anyhow.
