I feel like signaling only works in groups that signal. We've got plenty of signaling here on HN - open source projects, GitHub/CodePen account links, algorithm skill, fancy words, and people who choose to criticize whatever news is trending at the time (not directed at this comment). I've seen people screenshot their HN accounts together with karma score.

Someone on the outside looks at these signals and shakes their head, but it's just a bug in human nature.