For my piece on Catholic miracle apologetics, I read (correction: skimmed) a 25,000-word post by rationalist blogger Scott Alexander. My piece, which cited (but does not focus on) his, ended up being a cool 2,700 words. I don't think it would benefit from being longer, and it was the result of me cutting around 70% of the text I initially wrote.
Rationalist bloggers do not generally appear to have this impulse. Eliezer Yudkowsky's "sequences" are over one million words long. Nearly every blog post I have read in this ecosystem, even the rare one that contains some good ideas, is painfully long and extremely tedious. These bloggers tend to spend their time on precisely the wrong things, i.e. adding layers of detail and nuance rather than interrogating the one or two assumptions they make at the start or broadening their philosophical background beyond the collection of texts popular within their subculture.
It seems to me that, in this community, verbosity is a substitute for thoroughness: surely, if someone wrote a lot about something, and is able to demonstrate that by producing a large volume of text, they must have something worthwhile to say about it? Consider when blogger Gwern explained that nicotine, actually, is not addictive, and is good for you, as long as you don't smoke it, over the course of 9,000 words, with over 100 references. It turns out, actually, nicotine is addictive, and is bad for you even if you don't smoke it, as you probably already obviously knew.
In any case, what is missing from this endlessly verbose rationalist writing style is wisdom. Wisdom involves discretion: an intuition for what ideas are and are not worth seriously pursuing, and the ability to determine what does and does not need to be said. This community, broadly speaking, does not seem to value wisdom as a trait at all; the idea that something may be true, valuable, or good merely because it is common sense or inherited tradition is anathema to them. Instead, there is a heavy bias towards that which is unconventional and counterculture, with the amount of ink spilled for heterodox ideas taken as evidence in itself that these ideas are worth taking seriously.