Books have paragraphs, which are newlines and indentations, specifically to help people read in the face of what would otherwise be a wall of text.
Being able to read large chunks of text with minimal or no formatting is useful, but so is knowing how to format the text you produce so it's easier for people to consume. We should all strive to be capable of both.
Most books paragraphs are larger than an HN comment without spacing. Since the ability to read books is crucial, it is better to exercise the skill of reading text without spacing than asking commenters to add them.
Books have an incentive to minimize whitespace, as it costs money (paper). Computer screens don't have this limitation so the cost: benefit calculation is different.
What I mean is that book length content has paragraphs longer than single not spaced comments. Thus it is very odd that readers have issues with one but not with the other. Moreover making it too simple to parse comments and social network posts, creates users that struggle to read more complex content: as a society we don't want that.
In this case it's like if there were centuries of already written code with huge value, all written without comments. You don't want to limit the ability of programmers to read it. However things are very different in their dynamics: reading text without well separated paragraphs is mostly a matter of habit: a simple skill to achieve, so discouraging this ability has very little return. Lack of comments make reading code a lot harder in certain cases, especially since many informations in the comments are non local.
Also I'm not against proper formatting of posts. Just if it's not separated in paragraphs readers should so the small effort of doing it mentally, instead of complaining. Similarly I'm not against code comments (but strongly in favour).
Btw I replied for the sake of argumenting but the two things are not comparable. Just so this test: splitting text written by others in paragraphs is a very easy task you can do just reading the text one time. Commiting code you don't yet understand is impossible: many informations you should write are not implicitly in the code. It's the contrary actually: most good comments are about things that are not evident.
Redis is an excellent codebase and an extremely useful piece of software. I am a very grateful user.
I'm just mystified by the idea that functions, modules, and paragraphs are not only useful, but expected, while newlines in HN comments are not.
The best answer I can come up with is that internet etiquette and formatting is constantly evolving. If that's the case, I don't see the issue with suggesting a formatting that might be more effective or accessible.
Being able to read large chunks of text with minimal or no formatting is useful, but so is knowing how to format the text you produce so it's easier for people to consume. We should all strive to be capable of both.