OK, fine. ALL Orcs, Drow, etc are not irredeemably monstrous & in need of killing.
Just all of the ones I, as the DM, am going to throw in your path. Don't fret, you'll have good reason to kill them.
You say this as though it is a joke, but legitimately, this is all I think is really required.
The fact of the matter is the "orc children" or "goblin children" or "dragon egg" scenarios get discussed because DMs put their players in that situation. I've got no problem with all orcs I encounter being violent raiders, as long as I'm not put in a situation where I would logically doubt they are violent raiders.
Along with a meta-level acknowledgement that, well, good Orcs and orc tribes can exist. They might live "over there" and we never encounter them, but as long as we know it isn't ALL orcs, but just the orcs near us, then that is fine for over 50% of the problem.
Which they applied to all of the product. So yes, they're effectively calling every single thing created before 5th edition "Wrong". The key word would only work if it was applied to material which had some depiction of something that had a clear problem, like early Looney Toons, where almost no one would even try to argue that it wasn't clearly a problem.
They chose to apply it to everything, and that insinuates that all of it is wrong. To put it another way, you won't find a warning label "Product may contain nuts" in food that doesn't contain nuts, nor will you find a warning label about electrocution hazard on a product that doesn't use electricity. Warning labels aren't applied to things that don't have what the label is warning you about.
TSR contracts didn't involve royalties IIRC, and I'm pretty sure WOTC's don't either. It's very likely that WOTC not only slapped a label declaring their work to be wrong on it, but they probably aren't even making a dime off it.
Um, no.
First of all, I have seen many packages containing no nuts that contain the warning "Made in a factory which processes peanut oil" or other such variations. Not because the product itself contains nuts, but because it was made in the same factory, and some people are allergic enough that an accidental transfer could be problematic for them.
What WoTC disclaimer says is that some of the products contain depictions of racial, ethnic or culture prejudice that was common back in the day. This could be anything from an picture of drow with a specific style of haircut, to a specific cultural setting.
Those depictions are wrong, and not just wrong today, they were wrong back then too.
Does every work contain these? No.
Does every depiction of race, culture or ethnicity have prejudice? No.
But some do, and some of them are, and this is an acknowledgement of that fact.
Edit: You seem to have partially responded to this idea by saying that the analogy doesn't work because Peanuts can kill you, but stereotypes can't. My response falls under a different category altogether. I do not believe their needs to be a risk of hospitalization or death for there to be a need for warning labels.
You have it backwards. What you're doing is a version of the classic fallacy "dogs have four legs. Animals have four legs. Therefore, all animals are dogs."
I.e, since the dawn of time, human culture has depicted scary monsters as humanoids with exaggerated features to make them seem more scary. Eyes, noses, ears, fingers, arms, legs, etc. All human but misshapen. That doesn't mean they were depicted like that to disparage Jews. They existed before most of these cultures even knew who Jews were.
Instead, the pejorative depictions of Jews were done to resemble the monsters, for obvious reasons: to make people fear and hate Jews. This is true of every pejorative depiction of other ethnicities, from Africans to Japanese in WWII art. Exaggerated features to make them seem less than human. Does that mean every depiction of a goblin or orc or bugbear or kobold is based on those depictions? Of course not. That's silly. Just like it's silly to argue that the reason people don't like goblins is because they represent Jews. Monsters weren't meant to represent Jews, Jews were meant to represent monsters. Therefore, you can't argue with any authority that goblins are pejorative depictions of Jews because it's literally the other way around.
Also, there is plenty of evidence of games where Germans (or other religions or nationalities in wargames) are considered inherently evil and no one has expressed as adversity killing them as has people gotten upset about treating orcs and goblins as inherently evil. To say there is no evidence of what I suggested means you have no idea of gaming or games in general. I stand by my observation. More people have gotten more upset about the killing of fictional monsters than they do in games where real people are treated the same: inherently bad who need to he destroyed.
My suspicion about you not knowing about gaming history is doubled when you seriously argue that goblins in games and literature have never captured people and put them in prisons where they torture and kill them. That's a pretty common trope among monstrous humanoids. And appears over and over in just D&D alone. That, along with keeping people for food (which to my knowledge Nazi Germany never did)
I agree there is some backwards work, but you have to remember that the Jewish people (who I believe are ethnically the Hebrew people as well) have been around for a long long time. Judaism can be traced back to the Bronze age trivially. So, it is equally possible that the monsters were morphed by the stereotypes as it was the stereotypes morphed by the monsters. Both things could be true, though I am more willing to believe the monsters came first, since the stereotype for the Jewish people and money came about mostly because of banking and usury laws, which were fairly late in the game of myths.
But, I think you are also missing a rather clear point Sacrosanct. While, yes, propaganda went very fair in trying to make every German a Nazi, that was still never true. There were germans who helped the allies, many of the people fleeing were german, and by the time of WWII German's had immigrated around the world.
We tried to make all german's or all japanese the enemy, and that led to horrific consequences. Same as it has in the modern era with depictions of our enemies in the Middle East. However, except for the most egregious examples (which were mostly for the japanese) they have made sure to characterize is very careful. All Germans are part of the Nazi party, All Nazis are evil. A two step process. But, with fantasy races, they skipped the idealogical step. All Goblins are Evil. All Chromatic Dragons are evil.
And, this immediately causes problems. Let us say that the party finds a Black Dragon Egg. That dragon is evil. It has not even been born, has not taken it's first breath of air, and it is evil. It is capable of thought, choice, and emotion, but that is overridden by the fact that it is already evil before it was born.
On this very forum, in a discussion about necromancy, it was put forth to me that bringing an evil creature into the world is an evil act. Including if an evil creature like a goblin gave birth to another goblin. That is an evil act, because it brings more evil into the world.
No one has ever said that a person, even a german, was born a Nazi. But, goblins are. And that is the issue that gets pushback. Being born fundamentally evil.