I'd love to know why this happens so much. There's enough people in both groups that do spot it and don't spot it. I don't think I've ever felt the need for a sarcasm marker when I've seen one. Yet without it, it seems there will always be people taking things literally.
It doesn't feel like something where people gradually pick up on it either over the years, it just feels like sarcasm is either redundantly pointed out for those who get it or it is guaranteed to get a literal interpretation response.
Maybe it's because the literal interpretation of sarcasm is almost always so wrong that it inspires people to comment much more. So we just can't get away from this inefficient encoding/communication pattern.
But then again, maybe I'm just often assuming people mean things that sound so wrong to me as sarcasm, so perhaps there are a lot of people out there honestly saying the opposite to what I think they are saying as a joke.
HN has plenty of neurodivergent people and not picking up on sarcasm (especially without any voice data) is an autistic trait.
There is also a cultural element. Countries like the UK are used to deadpan where sarcasm is delivered in the same tone as normal, so thinking is required. In Japan the majority of things are taken literally.
Part of the problem is that sarcasm relies heavily on shared group values (common wisdom), to make it clear that a given statement is meant in the opposite sense. Our shared group values have been fragmented pretty hard (eg half the country has thrown away conservative American values in favor of open strong-man fascism). The icing on top is the tech-contrarianism that rejects common wisdom in favor of looking for an edge. It was innovative when done from the bottom up in a subculture, but it lands somewhere between tedious and horrific now that tech has taken over mainstream society.
The /s thing is the most surefire way to make whatever joke you’re making not funny at all, so I say go ahead and be sarcastic even if not everyone gets it.
And yeah, to your point about the literal interpretation of sarcasm being so absurd people want to correct it, I think you’re right. HN is a particularly pedantic corner of the internet, many of us like to be “right” for whatever reason.