Sure. On HN, after I worked in consulting and more specifically in automotive technology for a few years, topics would come up on which I actually had relevant

Sure. On HN, after I worked in consulting and more specifically in automotive technology for a few years, topics would come up on which I actually had relevant first-hand knowledge to share beyond what most HN readers and commenters would already know. At that point it seemed helpful to the community to share via commenting. Prior to that, an aphorism of a friend always seemed to apply - "his sum total life experience could be chiseled on the side of a toothpick". I.e. when you're young and just getting started on your career, you really don't know much of anything and acting as though you do just pisses off people who are actual experts and adds very little to a community.