Incidentally I am precisely looking for something like this so for me that’s valuable :)
A lot of advice that "You can easily do it yourself" presumes a fairly high level of skill and knowledgeable in sometimes multiple domains. That presumption isn't crazy talk for the HN audience. Plenty of people will have the requisite background knowledge to jump on a comment suggesting a DIY alternative.
But that in no way means there isn't a market for the product. Plenty of people may need or want X and not have the capacity to do it themselves, even with some instruction.
Further down someone has linked a couple other alternatives that are as easy to use as Stein, using a similarly neutral tone.
Dropbox came at a time when people were seeing the downsides of private solutions and the cloud was there to mitigate them. These days people are starting to see the downsides of relying on the cloud and are moving to private solutions.
The main difference is today's "private solution" is likely to be a self-hosted "cloud". So it's not that we're going back in time a decade, it's just choosing a combination of "private" and "cloud" that maximizes the advantages and minimizes the disadvantages.
All available evidence is contrary to this point.
But going back to OP's comment above and the link to the Dropbox topic, a decade ago many were not seeing the move to the cloud as anything more than a gimmick compared to the established private solution, not seeing the trend.
P.S. Just to be clear, by "private solution" I don't mean hosting in your own basement. It's retaining control over your solution even if it is hosted in someone's datacenter.