I recently posted the Wikipedia article for the Tesla Valve, an invention more than 100 years old, and it was upvoted a lot, and then I learned had been posted

I recently posted the Wikipedia article for the Tesla Valve, an invention more than 100 years old, and it was upvoted a lot, and then I learned had been posted many times before. I don't think the affair harmed anyone. Hacker News is whatever the community wants it to be. We have no obligation to ensure the title of the community conveys any information about our activities.