Update: Sorry, I somehow wanted to edit my text and couldn't.

Hi, I think a plug-in that gives an opportunity to give feedback about emotional manipulation is a good idea as well. As you said, such a plugin could hide content in non-cooperative websites directly, like an adblocker.
Some thoughts on what I think can increase the probability that something like this will be successful:

1. I think it is useful to have a "voting system for manipulation", instead of just trying to flag "clickbait" vs. "non-clickbait". With apologies:

"If only it were all so simple! If only there were evil people somewhere insidiously writing clickbait, and it were necessary only to separate their articles from the rest of us and destroy them. But the line dividing emotional manipulation and value cuts through the heart of every internet discussion. And who is willing to destroy a piece of his own heart?"

Every person who ever said or wrote something, online or offline, tried to use emotional manipulation (unconsciously) to be paid attention to (of course, you can find this in any of the messages written here). This doesn't mean the texts don't provide value to the readers or the world, just that the distribution of incentives is never the same for writer and reader. So I think the problem is not so much "articles that are obviously useless to everyone" (because if that was clear in the first place, they wouldn't appear on HN and noone would read them), but "articles that are useful to some people, but read by more people than that because they successfully manipulate their readers into acting against their own best interests".

The realistic goal is not "identify and eliminate clickbait/people writing evil things once and for all", but "shift the balance of power towards readers in our community" in the short term, and "improve alignment of the incentives of writers and readers" in the longer term. At the end of the day, all social progress (hunter-gatherer tribes, kingdoms, free speech, free press, separation of powers, democracy...) comes from (social or material) technologies that improve alignment of incentives between people. Internet communities had upvotes/karma for some time, but I think right now that these can be improved upon.

2. Such a system should initially be focussed on some adversarial (i.e. existing in order to make money/get attention for something else) website that is relatively small (more research/deliberation needed to actually determine a good place to start) and expand from there. This is for the same reason that Facebook was initially restricted to specific universities: If someone writes such a plugin and releases it with the immediate stated intent that the whole world uses it, noone will actually be concerned and sign up and no network effect can be achieved. If one first advertises it to a very specific community, people become more convinced that a network effect can be achieved, and are driven to sign up themselves. Once one has achieved success for some community, one could take

-feedback on improving the system, -social status of the idea,

and go on to fry bigger fish. And conversely, if one fails to get a network effect, one has "burnt" the basic idea and makes it less likely that such a project will be started/succeed in the near future.

3. I think it could be useful if the system allows users to organize into groups as well, and see only votes by people in their group. As in 1, articles are always useful or useless relative to the person potentially reading them. And all online communities degrade towards the lowest common denominator among their members, so it is desirable for the readers to keep that denominator high by encouraging separation into reasonable subgroups.

4. I am actually not all that concerned about people really behaving "obviously badly" - basically the only people who might be motivated enough to pay a sufficient amount of attention would be those working for the website directly, and for these, the risk to their reputation if they get caught is quite high. So giving users profiles (with the opportunity to convince other users of their humanity by a unique profile text etc.) and allowing to "downvote users" for suspicions of voting behaviour not in the interests of the group might be enough. Furthermore, I guess if this problem occurs, it will actually be a sign that the project was somewhat successful, so it is better not to be too worried about it right now.

So to conclude: Doing what you propose is not in contradiction to doing something specific to HN. In fact, if we come up with something new, and convince pg to implement it, and it turns out to be a success, this will gain information about whether/what/how such ideas work, and status for them, and actually increase the success chances of a larger project.