So, alright, speaking from real world experience here.
Coders shouldn't generally write documentation. It's often a mess. Sorry, coding folks. It is.
That's why you have tech writers. Like me. Mind, it's a shit job market because a lot of the higher ups think it's "useless," but that's for a whole other board.
But that's why you end up with those 4-page deep things because the coder is writing it from his brain. To a coder, those 4 page manuals make total sense. If you, the player, went to the coder and said 'Uh, this is confusing,' he'd probably be annoyed and wonder wtf was wrong with you. He wrote it! It makes sense! He knows the exact line you need!
But to the average person, it's convoluted.
You need that bridge person to write the documentation.
Unfortunately, in a hobby environment, that adds yet another task. It's basically adding another Staffer role/task onto the pile of stuff that needs doing. It's saying: we need someone who can learn every part of our code, what it does, and then write simple documentation for the players and rest of Staff.
As someone who has done this as a career, it's not easy work. A game would have to be a labor of love project for me to go from top to bottom to do so.
So while I wholeheartedly agree that it's a problem, it's not one that's a purposeful one. If you look at the help files for hard-code functions in Penn or Tiny... I can usually make sense of it in the right mindset (like my documentation writing days), but it's just a matter of being in that headspace. Which most people aren't. It's not a malicious thing.