You are assuming it is popular, and not that only a few vocal people are talking about it. Remember the HN community is large.
I use VSCode for most things, haven't tried the Jetbrains stuff much, besides in an interview where it worked "well enough".
Maybe eventually, I'll fork over and try the Jetbrains world. Maybe.
These days Jetbrains is just a default option for C/C++, Rust (Clion), Python (Pycharm), Java (IntelliJ).
Wondering what's so specific about HN crowd that makes Netbeans so popular here.