First, a softening up example: many D&D games involve duels, including duels to the death, and these are not treated as murders. No one thinks that a LG knight or samurai PC is doing an evil thing by fighting in a duel against a willing opponent.
I reject your idea that NOBODY sees that as wrong. I have played with people (mostly at Cons, but atleast once in a home game) that would argue that.
however yes, we do put some of our own real world morality aside... the more you ask for the harder the ask is.
Many D&D settings involve capital punishment - and in fact part of the logic of much "adventuring" in the classic vein of D&D is that it is retributive violence inflicted on the perpetrators of wrongdoing (bandits, Goblins, whomever).
this comes down to how your group feels... we long ago (end stage 3.5) realized we needed to use words first. We do what (We think) is a good way to handle it with 'excused for defense of self or defense of other'
we have not had a retributive death by a PC in a few years and you have to go back 15 years for it to be even more then once or twice a campagin.
As is well known, many people regard capital punishment as murder. But that needn't stop them playing D&D - because when they play D&D they suspend their real-world moral valuation and accept the fiction that capital punishment is sometimes permissible, and hence is not murder.
again most people don't want prisoners killed (not all there are people 100% pro capital punishment) the line with D&D again is defense of self and defense of other.
Strictly analogously, many people regard collective punishment - where people are punished for the wrongdoing of other members of their community - as wrong. Indeed, as I posted upthread, part of the point of a human rights framework is to transform collectivist social and political forms into individualist ones. But that needn't stop them playing RPGs set in Krynn (the Cataclysm) or Middle Earth (the Downfall of Numenor) - when they play D&D they suspend their real-world moral valuation and accept the fiction that collective punishment inflicted in the form of divine retribution is sometimes permissible, and hence not murder and a fortiori therefore not genocide.
this is a bridge too far for many...
and I would add that IF WOTC IS AIMING YOUNGER then it doesn't matter what 40's 50's and older players frequantly on enworld think as much as what teenagers think...
In other words, a D&D setting with capital punishment carried out by LG paladins doesn't ask anyone to entertain the absurd proposition that murder is good. Rather, it asks us to entertain the proposition that capital punishment is sometimes permissible.
do we have published settings in 5e with LG executioners? I only can think of Curse of Strahd and the Ice winter one and both if I recall are played as evil or at best missunderstood...
And DL/Krynn does not ask anyone to entertain the absurd proposition that genocide is good. Rather, it asks us to entertain the proposition that divine retribution carried out on a whole people is sometimes permissible.
and I propose that a majority of new players will not agree. (Not all)
In order to make it clear, I'll reiterate: someone who plays a DL game while accepting the conceit of the Cataclysm is not positing that genocide is good. Rather, the are entertaining, in the context of the fiction, the idea that the Cataclysm is not genocide because permissible collective punishment.
this strikes me as odd... how is a collective punishment of genocide not genocide? that also goes back to how is murder as punishment not murder?
I also remain puzzled that anyone who can't stomach that could nevertheless stomach entertaining the idea of LG paladins upholding the feudal order.
how many settings have real feudalism in it (offical WotC 5e settings) cause most have free land owners not serfs, very few have kings that have direct control... often they are city states with mayor/burgermeisters
