Is the headline being a straight-up lie a valid reason for flagging? The kid did not diagnose pneumonia. He came up with an idea for a design that might hypothetically detect pneumonia.
Unfortunately there is no other way to signal trash submissions. "Not upvoting" is not really a sufficient signal when enough people get baited by the headline.
I agree, but I highly suspect that if you flag a lot of submissions that aren't also flagged by others you end up on some kind of list where your flags are ignored or deprioritized.
I've mentioned this elsewhere but I think Hacker News needs people who are vetted users who can flag these articles with specific bits, such as "this is clickbait that oversells what happened here", or "this is an unnecessarily partisan analysis of COVID policy outcomes". That signal is much more important to me than "this post was flagged because people don't like emacs"