Being positive and supportive is a good quality, but it is not enough to make a comment good. Comments are supposed to have thought and substance too.

Shallow praise is better than a shallow dismissal, but not by enough.

That's too harsh, and not in the spirit of the site. Right from the beginning, pg made this distinction:

Empty comments can be ok if they're positive. There's nothing wrong with submitting a comment saying just "Thanks." What we especially discourage are comments that are empty and negative—comments that are mere name-calling.

https://news.ycombinator.com/newswelcome.html

https://hn.algolia.com/?dateRange=all&page=0&prefix=false&qu...

I'm pretty sure I've seen dang or pg say that quick, low-effort comments that express enthusiasm for a comment or post are fine (whereas low-effort, drive-by dismissals are very much not fine). I've tried searching but it's not obvious what search terms would turn up such a comment.

But I hope my recollection about that is right. Yes we want comments to be substantive in general, but we don't want to be surly or even Grinch-like when someone is just expressing excitement and affirmation for someone else's contribution. I'm sure that's not what pg or dang would want here.