I wonder if this is done on purpose, to nudge people into thinking of individual users not as people but as voices of a "hivemind".
Even today, usernames are de-emphasized in the UI in contrast to names of threads or subreddits. That's most prominent on the front-page ("r/all") where posts don't show the usernames at all, only the names of subreddits - producing the odd impression that the subreddits are authoring the posts and not individual users within the subreddit.
HN's UI is sort of similar on the first half: Users are de-emphasized here as well, but there are no subreddits to emphasize instead. Though I think it would be interesting if someone made an alternative frontend for HN that presented threads in the style of an old web forum, with user identities shown prominently
I think it works frightenly well sometimes. Ask yourself:
- How many engaging conversations have you had on HN in the last year?
- How many people do you know on HN?