The best way to help FreeBSD (or any open source projects in general) is to submit diffs to the project documentation itself, than to have lots of documentation scattered among blogs (which will soon become outdated also).
The project benefits by having up-to-date documentation, the users benefit by having a single source of truth and a lot of questions in the mailing lists are saved by users not following documentation which probably are no longer relevant.
I haven't used FreeBSD in quite a few years, but I'm sad to hear it's no longer what it was :-(
Looking at the source it looks like they went from the obscure SGML to ... some obscure XML. The entire thing looks horrible and a pain to edit, so I'm not surprised that few people contribute (including the OP).
While they are less powerful, markdown, restructured text and other simpler markup languages are much more productive to work with. They are easier for beginners to understand, and the markup is sufficiently lightweight for most of the common cases that it doesn't interrupt your train of thought while trying to think about how to best describe complex technical details.
Which isn't to say it's not very good at what it does, just that I can't see a compelling difference over DocBook or HTML.
There was time when VirtualBox was not available on FreeBSD, no one even thought about writing Bhyve and QEMU was only 'virtualization' option on FreeBSD (with KQEMU accelerator module).
As I used FreeBSD I even made a howto - HOWTO: QEMU on FreeBSD - still available here: https://forums.freebsd.org/threads/howto-qemu-on-freebsd.175...
... and someone suggested just that, to add my thoughts/changes to the FreeBSD Handbook.
... so I did sit down and rewrite entire 'Virtualization Chapter' in HTML, still available here: http://www.strony.toya.net.pl/~vermaden/FreeBSD-Handbook-Vir...
... and no one done anything with it.
It was not merged, not a single bit from it was merged into the FreeBSD Handbook.
When I asked why I got response that maybe if it was in the correct format (I do not remember which documentation framework FreeBSD used back then) some parts would be used but as its in HTML no one will even 'waste' time merging it. I did the most 'hard' part which is creating the valuable content, formatting is secondary thing for me, but it was not for them.
Since then I do not bother about FreeBSD Handbook. I still use it from time to time thou. I would not have anything against even if someone would put my entire article there without any changes, that would serve a lot of people, but if someone will do it, that I do not know.
Consider the code version of what you linked above. Imagine submitting a patch in the form of an HTML post on a private website (wrong format), in poor and non-idiomatic style (both for the project and the language itself), full of typos and grammatical errors (bugs?), with the author themselves professing that it's "nowhere near finished".
If someone submitted a patch to any serious open-source project in this form, they'd tell you in one way or another to come back when your patch was finished and was written in accordance with the standards of the project. You haven't done most of the hard part at all: you're complaining about their lack of gratitude for the beautiful lamb dinner you've cooked for them, but really all you've done is dump a lamb on their doorstep and expected them to shepherd it, slaughter it, and prepare it.
(there's a flip-side to this: while the original comment you're replying to is right that (properly) contributing to the official documentation is the best way to support it and better than writing up a blog post, it also presumes that we all have the time or energy for that kind of commitment, which is much greater than that for just writing up a blog post.)
If you had obtained the handbook from version control, and added this as a new file using the markup language in use, made sure it built without warnings or errors, proofread the HTML and PDF output, and then sent that in as a patch, it would have been mergeable with no effort other than a brief review.
If the people reviewing it also had to completely rewrite it in the correct markup language, and they are not domain experts in the material it is covering, then you've basically given them a task which is hugely demanding upon their time.
I've had several experiences of this. Sometimes it pays to pull all the stops out and spoonfeed the recipients with something which is as perfect as it can be, and they have no reason not to merge it. It takes a lot more time on the part of the submitter, but that's time you've saved the reviewer, by giving them a finished article. This can greatly improve the chances of success, by removing obstacles which would hinder it.
I see that there already is "an aggregation feed of dozens of blogs" linking to planet.freebsd.org which does not respond :)
There is also FreeBSD Community Resources wiki page - https://wiki.freebsd.org/Community/Resources - which contains links to such blogs and resources.
That lefts OpenBSD users with software containing security holes and bugs. IMHO OpenBSD should create a pkg(8) equivalent (or even port it/import it like openssl) to have up to date packages at least for RELEASE.