I would say both cases has far less to do with the anonyminity or lack there of. HN is a heavily moderated board, with things like trolling, offensive comments, non civil discourse, etc, being stamped out fairly quickly by the moderators (who, by and large do a decent job, even if sometimes they get a little heavy handed). Whereas on most local news sites, that’s just not the case. Presumably they thought having a “real name” to the comments would temper people a bit, but by and large, we’ve seen that’s just not the case.