HN doesn’t really distinguish between “punching down” and “punching up”, and prefers to avoid “punching” at all.
The guiding principle to keep top of mind is “intellectual curiosity”. There’s a place for an intellectually curious discussion about the history and present day meaning of the word “shibboleth”, and the way you commented brings that to a screeching halt. And even if someone else seems to be acting like a bit of a jerk in the comments, it doesn’t make it OK to do it too.
But as you say, you’ll try to do better which is great.
I don't think I've knowingly punched down.
Edit: anyway noted. I'll try to be more American (in the old sense; I'm not sure being Trumpian would work well here!)