The difference may be that you, who know more about these things, have in your head the state needed to appreciate the statement. The comment may be brief, but that's because it's compressed, not because (for you) it's shallow. It's like the old joke where the prisoners know all the jokes so well they just call them out by number.

But those of us who know less don't have that information, and since the comment didn't explicitly deliver it, there's no way to learn from it. What to you is a compressed valid opinion ends up landing like a shallow dismissal.

What works better on HN is for the commenter to share some of what they know, so the rest of us can learn, and so the comment itself becomes substantive with supporting information, details, etc. Then we won't just know that you disapprove of, e.g., a particular aircraft design, but will also have some idea of why.

It can be hard to remember to do this, because most of us take the extra state in our heads for granted.