Upvoted to the front page, holding there for hours, people were having a discussion about the appropriateness of swearing in this context, the extent to which it was a joke, and about how NVIDIA has treated the Linux community. And, of course, then the title changed: it got reverted to something like "Random Panel from Random Conference".
Now, everyone was really confused: the comments were all concentrating on this one moment in an hour long video (linked to semi-directly, but still like 30 seconds after the link), and freaking out about how people were so uptight and shouldn't be concentrating on that, and that there was all of this other content there.
When the title changes, it drastically changes the character of the discussion: while this website is also a link aggregator, I know of very few people who believe that that is its value; instead, people like Hacker News because of the comments: it is a discussion forum. You can't just change the title of the discussion forum while people are actively discussing things without causing a catastrophic situation.
This is thereby what I mean by "transparency": I don't mean a moderator spending even an extra 30 seconds explaining "why" something happened... I just mean that the site needs to make it clear that something did happen, or these massive arguments break out and a bunch of people are left unhappy and angry. As long as title changes are going to happen to discussion threads that already have hundreds of comments, you at least need to have a boolean "title changed" notice.
That aside, the "nuance" aspect (which I think is even more important than the "transparency" part, as you might just decide "old posts should never have their title changed" and the transparency is less important) would probably require more time from the moderators. I am not certain how to get around that: I think moderation fundamentally requires nuance.