In the last few years I think the amount of "pure" programming related posts on HN has dipped. Out of 30 items on the front page right now, only 4 are explicitly about programming (I'm not including ops/networking).
(This is only gut feeling from being here a long time, no data to back it up.)
https://toddwschneider.com/dashboards/hacker-news-trends/?q=...
All of them seem to have a downtrend from around 2012.