I expect it is bad form to reply to yourself but I've changed my opinion and no longer object to the post title. I think this reply better reflects that than a mere edit...
Not to put words into anyone's mouth but if I imagine what dang or someone else with a similar position might think in response to my post above:
The goal with the title of a post isn't only to accurately convey what the linked content is, but also why it is interesting and belongs on Hacker News and do both of those concisely. And while both the title and content of the article might wander into cliché, framing everything in the context of change, some things that are just plain interesting are included and those are the main reason for it being posted here. I think it is easier for me to recognize that when the post title adds to or modifies the original, pointing at what makes it interesting rather than removing something. But I can see how in this case removing from the article title achieves the same goal so it seems in keeping with the goals of this site.
Oh, and finally I misunderstood the comment about "not part of the diff". I thought dang was pointing at a history of edits to the post title showing he merely chose not to alter the original post title which already differed from the article. I should have followed the link which I appreciate. Though it also makes me concerned about how we can fight the novelty bias it introduces which I think our society and the tech industry in particular suffers from.