I feel like there are more brief and superfluous comments than there are used to be, but just as many or more lengthy and substantial comments.

Your comment gave me an interesting idea. What would happen if we imposed a minimum char-limit for say, hacker news comments? On one hand I'd expect more descriptive responses, fewer comments that are a short "Your wrong but I won't tell you why", etc. Comments just spamming letters would be fairly easy to detect.

On the other hand what would this minimum char/word length be? Even your comment is fairly short, but it's descriptive and fully communicates your point...

Then you end up with comments like you find on leasehackr.com, which has a twenty character minimum: “Agreed. 202020202020”

I believe there is a minimum character length under which comments are printed in a smaller font. I’m sure the mods have some insight into this.

Huh. I've only been here a couple of years, and I feel the quality of discussion is already starting to worsen. (However, it's still better than most other things—see https://danluu.com/hn-comments/)