I didn't see his suggestion as bleak/dark/edgy.
Just a logical conclusion drawn from a race as implausible and perfect as the elves.
You can't have a race that is simultaneously: 1) in "harmony" with nature 2) perfectly beautiful and clean and above mortal concerns 3) possesses a vast amount of mineral wealth, finely worked goods, etc. 4) is a paragon of holier-than-thou moral virtue.
These are not really compatible. For one thing, nature is incredibly hostile to any sort of civilized life. To achieve great works, you need to subjugate nature. You also need to be willing to get your hands dirty by mining, smelting, farming, etc. So you can have #3 and #4 at the expense of cleaving closely to #1 and #2, for example.
Basically... The only way to have all of those things is for one or more of them to be a facade. His suggestion that #4 was the facade, which is in my opinion kinda clever and novel.
You can't have a race that is simultaneously: 1) in "harmony" with nature 2) perfectly beautiful and clean and above mortal concerns 3) possesses a vast amount of mineral wealth, finely worked goods, etc. 4) is a paragon of holier-than-thou moral virtue.
For one thing, nature is incredibly hostile to any sort of civilized life. To achieve great works, you need to subjugate nature.
Every elf is either a ranger, a wizard, a cleric, a bard, a fighter, or an artisan of some sort.
There is tremendous discipline instilled in them by the society as a whole.
4. They keep the population down one way or another.
3. Lots of space-assuming a human like diet you need a few square miles per person.
I like the comparison to the advanced, hunter gatherer societies. I don't see elves, farming at all.
Every elf is either a ranger, a wizard, a cleric, a bard, a fighter, or an artisan of some sort.
I don't see why there is any disconnect. For what it's worth, the "harmony with nature" bit is really just a function of low population, large territory, and minimal infrastructure. "Perfectly beautiful and clean and above mortal concerns" is a perception, elves themselves probably don't regard themselves as such, or if they do, it's a byproduct of other races finding them thus. They are gracile and have refined features, that's just anatomy. As for their mineral wealth and such, they have very long lives in which to accumulate it, and many skills with which to trade for items they don't produce themselves. And as for paragons of holier-than-thou moral virtue, again, I think that's just personal perception.
I think elven societies appear "too perfect" by some standards because every individual is highly trained and highly skilled. There are no elven "commoners" sitting around selling sausages to tourists. Every elf is either a ranger, a wizard, a cleric, a bard, a fighter, or an artisan of some sort. They invest in each individual, and they train their children rigorously. There is tremendous discipline instilled in them by the society as a whole. Those elf individuals who can't fit into this framework naturally leave elf society and become adventurers. But YMMV, if you just don't like elves I can't convince you that my perception of them has any merit.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.