I recommend all the downvoters to look up "/s".

Maybe it's the sarcastic inverted interpretation that is being downvoted?

Or perhaps that the comment adds nothing to the conversation?

I would disagree. I remember for example how the discussion was about how the various pharma companies make lots of private money with the vaccines, but did receive generous government funding - and how the comment, also here on HN was: whatever, as long as the pandemie stops. And we are talking about a Corona app here.

So I think the sarcarsm was valid ... but probably not the whole discussion about

I downvoted because I hate the use of /s

How would you recommend to indicate sarcasm in the absence of nonverbal cues which a written medium necessarily entails?

My guess would be that they dislike sarcasm in general.

Yeah I just totally hate sarcasm, has nothing to with /s being overused where it's super obvious.

This got too meta for me now. /s