Hiya!
EDIT: It also occurs to me that "world of hurt" means different things to different people; to me, it doesnt' mean "death and dismemberment", but more of a Homer "DOH!" mental-anguish type of thing. Just needed to clarify that I think.
To me, this feels like the DM handing out homework, expecting me to memorize minor factoids, and then sneering at me if I don't remember minor details from some paper almost a month ago. And it goes against the idea that the characters are supposed to be individuals living in the game world instead of purely avatars for the players to play the game; whether the player remembers obscure details from the handout, the characters should know. I'm not saying 'you're a terrible DM and you shouldn't be allowed within 100' of a DMG' (this is clearly a legit playstyle), but I am saying that I would just stop playing in a game the first time 'you're in a world of hurt because you didn't remember specific information on the handout I assigned a month ago that your character would know' happened. I play games for adventure and general escapism, and this really would not hit the mark for me or a lot of people I know.
I can understand that perception. But then again, "anything" can be considered 'homework' if the person doing it isn't interested in it in the first place.
I mean, "Ok, you're new to D&D. Here's the main book for players...the Players Hand Book. Give it a look see, read what you want and think about the character you might want to play". <-- could be "homework" to some people. I actually had one player, a girlfriend of a friend, who was quite annoyed at having to actually read anything in the Basic Players Book (out of the Basic Box Set #1)...including what her character class actually was. She enjoyed playing, rolling dice and making decisions, you know, all the actual "game and roleplaying stuff". But getting her to read what the "Magic Missile" spell did...you'd swear we were asking her to read War and Peace!
As for ME and my DM'ing style... rarely (ever?...I can't remember it ever happening...) will a PC's "death" result from the Player not knowing XYZ about factoid ABC from country 123. It's usually just a benefit. I might say something in passing like, "...and at the end of the dock is a ship flying a flag of a black, four-pointed wavy star on a red field" after describing a few other ships with their flags. Now, if the PC's were involved in some "shenanigans" that involved trouncing a couple of Scarlett Brotherhood theives/assassins/monks a little while ago...this might give them a heads up to keep their heads down. But if the Player(s) DIDN'T recognize the standard on the ship...it's not going to "kill them"; it's just information that might give them a bit of a tip.
So, I guess you could say it's "good to be informed...but it's better to be lucky".

As such, my players and our general "Play Style" is much more old-school, which involves a lot of questions. Newer players, I've found anyway, tend to rely on the DM feeding them the "needed information" for whatever quest/adventure they are on. Just yesterday I FINALLY managed to play with my bro and his group online (Fantasy Grounds Unity; 5e game). I could tell that all of the other players other than my bro and maybe one other guy, were all "new'ish" (re: learned with 3e or later). Very little in the way of "mundane questions"...usually their questions were specific to the immediate focus (re: "How far away is he from X?", "Is it a stone or wood fence?", etc). I think I caught them off guard when asking and doing stuff that had 'nothing' to do with the immediately obvious "pointer", but had to do with more NPC motivation, backstory, world info, city laws, etc.
Anyway...bottom line...: My Players might find the "world history/background/info" to be useful and beneficial to them...but not "necessary for success/survival". That's all.
^_^
Paul L. Ming