I think things like that should be easy to say, if by that you mean censorship. Sure. But talk is cheap. And there are gradations of reality.

It would maybe be easier for a 15-25 y.o. to kill a baby they don't know and whose parents/family they don't know, and maybe even easier if they don't speak their language or look like them. Of course, the baby wouldn't be the only one you'd have to kill, most likely.

I submit that it would be very very different if you found out that your 4 year old child was going to go on to be the next Hitler. For a "normal" person, I think they would go to the ends of the earth to try to shape them into the kind of person that wouldn't do it. I think very few people would coldly calculate "welp, guess I gotta execute this adorable little child I've grown so attached to" as it looks up at them saying "I love you so much forever, mommy/daddy" with their little doe eyes.

(ETA: it also brings up side questions about nature vs nurture and free will)

And then consider the lifelong repercussions of the emotional fallout. You can use all the logic in the world to justify the action, but your human brain will still torment you over it. And likely, most of the other human brains that learn about it would torment you as well.

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So, while I think you can say things like that, ie the ability and allowance, I think you should question whether you should. I think saying those kinds of things really doesn't add much to the discussion because I believe it's really just an uninformed platitude that only someone with a lack of life experience would believe.

For me this all highlights the fact that meaty ethical questions don't have a simple reductive answer. Which ties back in to the original problem that OP outright states that this is simply and clearly the wrong path to go down.

(PS the downvoting/flagging could be due to breaking the guidelines around discussing downvotes and flags, and not actually due to the topical content of the posts, and/or assuming bad faith on the part of other users as such: https://news.ycombinator.com/newsguidelines.html)