There is some kind of massive brigading happening on this thread. Lots of thoughtful comments are downmodded or flagged (including mine, which I thought was pretty thoughtful. I even said poop instead of shit.).
I addressed the entire concept of the talk, and made other relevant points. The correct response to "let me tell you something I can't possibly know" isn't to argue the points within that frame.
If you see a talk like: "How we will develop diplomacy with the rat-people of TRAPPIST-5." you don't have to make some argument about super-earths and gravity and the rocket equation. You can just point out it's absurd to pretend to know something like whether there are rat-people there.
I've noticed that Hacker News has become increasingly strict with tone lately; almost to the point of aggressive "tone policing." It feels like you’re expected to maintain a very diplomatic tone: praise the author, acknowledge the strengths of the article or video, and only then, very carefully, offer any criticism. You can't just bash it, and not get downvoted :)
https://news.ycombinator.com/item?id=44492241
My comment was basically instantly flagged. I see at least 3 other flagged comments that I can't imagine deserve to be flagged.