Since the start of the COVID-19 pandemic, I've noticed a lot of preprints seem to be getting shared and promoted, and the interest in bio/med research has naturally spiked. I think it's good to have a reminder that preprints are not peer reviewed, and that you should be very careful as to what conclusions you draw from preprint publications, especially in ones outside of your area of expertise. Peer review isn't perfect, but there have been some recent threads on HN and news stories based on preprints with glaring issues that would have been caught in peer review. Furthermore, even peer review not being perfect should give you a reason to pause and reconsider how much weight you want to give individual articles, especially ones that haven't even gone through that most basic filter of being read over by a scientist or two before being plopped into a megajournal somewhere. There's a lot of incentive for people to publish big, eye catching conclusions, especially right now, so it's a good idea to both be cautious of anything you read in a preprint and pause for a second before sharing a preprint with a stunning finding.
Also, - could it make sense for HN to have preprint submissions have a tag like [PREPRINT] in the title? So people scrolling through and just reading titles would have a quick indication of what headlines are based on preprints? It could be helpful in providing the context necessary to interpret links shared to HN and to fighting the spread of misinformation or bad science.