I know exactly what you’re talking about. But the last time I actually had a handbook from a game in my hands (Falcon 3.0 FTW!) was in the early 90s or so (okay, to be fair: I also “stopped gaming” in the mid 90s).
And you know what else was very different back then? Exactly: “no widespread internet”! That means you got the game on floppy disks (anyone remembers those? It’s sometimes still represented with that funny icon on that button where you save your documents ;)), and later on “multimedia CDs” (with sound and, oh, movie sequences - imagine that!)
And after that you got perhaps a patch file from some CD-ROM that was coming along with some “gaming magazine”. Or the “internet pioneers” who were not afraid of costly phone bills even downloaded those patch files from some FTP server (the address of which you again figured out in some gaming magazine or so…).
But the game was “mostly finished” back then. You got what you got.
Now compare FS2020 today with the initial release: most menus are already different. The keyboard/mouse interaction changed. You have more airplanes, more airports, more scenery (okay, you wouldn’t probably document the available scenery in a handbook ;)).
You get where I am going with this: a 300 page handbook from August 2020 would only be worth its energy equivalent when you would burn it in a fire! And the same goes (hopefully :)) for a handbook released today…
So yes, times have changed. And so did games: it is a “continuous development” (for the better or worse). Personnally for games like FS2020 I think that’s the only meaningful development model, for such “monumental developments” (which are associated with a LOT of RESEARCH, mind you!).
Oh, you are talking about this here?