One of the main differences is how the pulp fantasy novels treat interior 'psychology'.
I broadly agree but I do not think the issue itself is the focus on character psychology. In a long running series its basically impossible to not tackle it unless you keep constantly swapping out characters. In fact in a long running I would be just straight up detrimental to no pay at least lip service to it.
The real problem is that said psychological focus is used in service of a deconstructive or rather destructive goals.
To give a simple example of what I mean:
Modern writers call this "trope deconstruction" or more recently "subversion of expectations" but what they end up doing is just destruction. Because to de-construct you first need to understand the construction itself. In writing this would be successfully being able to take a trope and build stories around it and understand why and how said tropes even exist. Only after that you can start deconstructing anything. Without that first step you are just destroying the old trope without really replacing it with anything.
To be more specific, take the orcs. The classic trope of orcs is a set of characteristics that ultimately paint the orcs as a force of nature that is about as strong as the humans. They are still wild, unpredictable and naturalistic as a typhoon but they exist in a way that the hero of the story can realistically tackle. This then further informs the attitude of the broader fantasy world towards them, their look and the way they are used in the story.
To deconstruct this you would have to keep all the existing characteristics but slot them into a different or broader context. For example you could make the point that orcs are objectively evil and animal like but as an active part of the ecosystem that helps prevent other problems from growing out of control(in case of D&D lets say it the giant wolf population). Or you can make the point that without them there is nothing uniting the many different fantasy races together and a much worse conflict would arise without them. Or you could take a moralistic stance and argue that if you cross the threshold of genociding one race what is there to prevent you from genociding another and another?
What the comic and most modern writers do however is that they flush the whole concept of an orc and just make them into regular dudes who just happen to be green and (sometimes) ugly. This just completely removes the trope. Nothing is deconstructed because now that orcs are no longer savage beast but just green dudes a world and narrative built around the assumption that they are beasts no longer works. Sure they are now more complex and "psychological" characters but that is at the expense of everything else. "Expense" because once the writer is OK with breaking one building block of his narrative there is nothing keeping him from doing the same with all the other blocks.
The addition of psychological focus is not the problem. The reason why and how is.
The end result is a work of fiction that is dysfunctional both internally and externally. Internally its a mess of contradictory plot points/ideas and externally in the author's head its a dunk on something that exists entirely outside of the work itself(and mostly also the perspective reader).
Some people have taken the piss in the past for me saying this, but I think that
geeks represent the last sub-culture in the West that longs for the medieval spiritual perspective, which they channel into love of adventure fiction, science fiction and magic. Contemporary mindsets just cannot understand the medieval; hence why some just don't "get it" and pooh pooh fantasy, preferring some film about money and cars. They seek to "humanise" things, injecting 'irony', when the things were earnest and symbolic. Orcs were not a race. Orcs were a mytho-psychic symbol. Thus humanising them utterly misses the point entirely, to a massive and stupendous degree. A modern egalitarian raised on Marxist 'historical materialist' assumptions as most Hollywood writers and English lit students are, just cannot see anything symbolic beyond the material.
The way the gentleman in the video puts it is that balanced fantasy contains both contemporary people like Han Solo, and pure archetypes like Emperor Palpatine:
Also a person attains apotheosis into an archetype by actually moving along the spectrum from an "all too human" contemporary into a living symbol, as Luke Skywalker did. He starts out as a whiny contemporary not wanting to stay on the farm for another season, and becomes a stoic demi-god. But what motivates people to again and again "humanise" Orcs, is that some people in life just cannot see or understand anything beyond materialistic conditions. They attribute everything to social circumstance, so cannot conceive of a symbol of entropy itself, like Sauron or Palpatine or the Orcs. So you get "noble savage" Warcraft 3 Orcs that were simply "misled" etc. Tolkien Orcs are pure archetype, they don't actually have existence as a material race; they are a pure symbol.
I agree that deconstructionism is a major problem, but have a completely different idea about why, and it's value. To destroy is always easier than to create. Deconstructionism, I suspect, was purely in most cases, a weapon for casting people's morals into doubt, to ferment resentment for a host of reaons. In genuine works that reach toward a supra-human truth, such as Star Wars and Tolkien, the deconstructionism is usually mistaken, a simple inability to see the symbolic, and to reduce it to human proportions by myopic people. The healthy form of "deconstructionism" is just called "honesty".
So what the hell is wrong with a race or species being inherently evil?
It could be due to supernatural causes or the malevolent influence of some other dark beings (such as demons) afflicting that specific race or species.
Reminder that demons in oldschool D&D used to be CHAOTIC EVIL and were made from the raw stuff of the Abyss. They cannot change their alignment nor their morality, as it would probably require the intervention of a deity or some other higher power.
It need not even be reasoned in such cause and effect material ways. A barrier exists between the mundane profane world and the mythic. Like how the Celts saw the otherworld as being a place that could be accessed through caves and lakes. In Star Wars, some characters are human, and some like the Emperor, are not actually human but symbolic and on the other side of the veil.
You don't need to say Orcs are evil "because... XYZ" (they were corrupted, they were possessed by demons, they were infected by a dark plague). You don't need to explicitly say what character is on either side of the veil, you just need to know who is, and treat them as a different catagory of thing, a spiritual being despite them being materially justified in an apparently materialist setting.
So what the hell is wrong with a race or species being inherently evil?
It runs counter to the current ideology of absolute equality and perfectibility.
It's been clear to me for a while that this is a side-artifact of the unwillingness of the (broadly speaking) Left to let go of the myth of equality
Yes, this is a big part of it.
All peoples and societies have idols they can't stop worshipping. For the modern, it's egalitarianism that has the biggest hold. People would turn to worshipping another idol in it's place perhaps, but right now, an inability to treat say Orcs as a symbolic evil race, is rooted in an extreme idolisation of the concept of "equity" above truth-reality, to the point where anti-egalitarianism, in any realm, constitutes a massive threat to their ego-identity.