Correct me if I'm wrong, and I can be very well wrong as I don't dig and study as much as all of you into this stuff. But there has always been a debate between a Railroad and Sandbox type style play....right?
Me personally, I'm in favor of Sandbox play. Others can play however they want, as it doesn't affect me.
To me, Sandbox play is the epitome of letting the players have choices. When a DM supplies situations, hooks, what have you, the players ultimately create the story (that most interest them) by their choices. The adventure's plot (or DM's plot) is in the background...maybe followed, maybe not.
So...I will now start the debate that painting ALL humanoids as evil....to me, that heavily borders on Railroad play. It reduces choices. It reduces roleplay (i.e. I just slaughter them all because they are evil). It makes faction play in Caves of Chaos obsolete depending on character class/alignment....why bother working with them, they are evil and we are good, lets slaughter them, etc.
I understand the distaste to have a special snowflake character who might be a orc or whatever...my response to that during play is to not go easy on that type of character and the trust takes forever to build and sometimes it doesn't, leading to PVP. But part of D&D to me is exploring and the 'awe'....and part of that 'awe' for me is trying to figure out how my character is going to deal with strange situations (i.e. a orc character that wants to join the party)---most of the time it's from the DM, but other times, its from the other players who are actively building the story and world with their choices and actions. The debate between players having a orc character join our ranks and the roleplay from the situation adds to the game for me--or adds to the 'awe'. Can you fully trust this orc?---it adds to the tension, especially when players get into their quirks of their characters.
I was reacting to this:
"...A legendary hero is summoned to aid humanity against an irredeemably evil race of beings only to discover that he has been misled and that humanity is actually waging a war of genocide against innocent people."
I've picked a side in the culture war. I reject of this sort of hippy 1960's anti-Western attitude (that I once wholly embraced---as instructed in college & by progressive 1970's Hollywood). I think it pretty much always takes humanity to a darker, sadder result. I prefer a more optimistic future, not a slow spiral into collective misery. I don't need this kind of negativity in my head anymore. e.g. Elric as an evil drug-addicted Prince where everything ends badly always felt like a bitter old Moorecock just pissing on a world he hates (and then wanting to be praised for it).
I just need something more uplifting, life-affirming, and less "mature" in my fantasy life. There's enough darkness out there already.
Playing a legendary hero can be fun...and there is absolutely nothing wrong with that type of game play where your group is a bunch of heroes. A good DM can add enough challenges and situations to support that type of play.
But having a hero 'misled'....I just don't really view that as a culture war (and there is alot that I view as culture wars lately, which is dumb and I get mad at myself, because this is a game). I could view that situation as interesting...and helping with the "awe" factor. If every situation leads to that--sure, that can get old and boring as well and some eye rolling can occur on 'trying too hard' with the grimdark. Uplifting moments can be key too, and there should be a balance.
But the bottom line for me, is when the DM does a superb job of creating the scene/situation and sometimes able to just sit back for 30 minutes to an hour and watch the players build the story and roleplay amongst themselves off the tidbits you fed them...And sometimes that happens, by adding a helpful orc or something a bit out of the ordinary for the party to deal with. To me personally, it just makes the world feel bigger and choices having a bigger impact.