HN prefers to use the titles from the original site.
Also, many titles are context sensitive. For example, if you're reading the title on the Quill website, chances are you already know what Quill is - or do you? When you copy the title verbatim to something like HN, the context is completely lost to anyone who doesn't already know what Quill is. In other words matching the title doesn't benefit anyone when the title is meaningless without context.