Hey, spleen! Details on dragons in this universe please.
Dragons are (or were, to be more precise) just a fairytale. Similar to us, they're mostly a culturally relevant creature that was likely conceived from a few dinosaur bones. The basic beats of a dragon can be found in there, mostly in the way of the wyvern (that is to say, two legs, massive wings, tail, breathing fire, et cetera). They are massive creatures, their skin is like ten-fold shields, their teeth are like swords, their claws spears, wings as a hurricane, and their breath death. You know, the basics.
The thing is, that shit doesn't add up. For one, for a creature to be as tough and huge as that, it would have to be monstrously dense. There is no wingspan possible that could even hope to carry that kind of weight, and that's not getting into the insane musculature that would be needed to even keep those wings going. The metabolism of that creature would be insane, you could feed it a forest and it would still be hungry, especially if it simultaneously has to produce a constant stream of fire. Speaking of which: the fuel needed for that kind of power would make the dragon highly explosive. Considering that they tend to be in a situation that causes a lot of heat, they should outright explode most of the time.
They were simply not feasible without a ludicrous amount of magic. This world has a lot of magic in the air, allowing for some truly fantastical creatures (like driders!), but for a dragon to exist there are so many things that it couldn't just handwave away. Two different types of blood, or a human brian that shouldn't be able to handle eight limbs? Sure, it'll work out. The metabolism needed for that? We'll gloss over it a little. Keeping a dragon alive requires far more magic than the world could provide, and nobody was ever stupid enough to create something like that. A lot of magical creatures even have their origins in aeons-old flights of wizardly fancy. Driders started out as a personal fetish project that got kind of out of hand and ended when the tendency towards cannibalism manifested itself.
But I digress. The point is that dragons are only possible through an impossibly massive influx of magic. This is a direct result of the Gestating God seeing a hole in the defences because of some rookies set for the Darkest Dungeon let an infected lady go without a proper check. Spending this amount of magic is exhausting even for an eldritch God, but it manages to regain most of the magic lost through the magic now spread throughout the world.
Yes, it basically auto-cannibalized itself to regain its strength, eldritch creatures are pure bullshit.
As a result of that massive amount of magic needed to sustain it, it took on the most common fairy-tale rendition. And as it turns out, The Hobbit is really popular in this fictional universe, go figure. Of course, the eldrtich quality means the dragon is probably a little more fleshy and disturbing than you'd think of, but most of the beats are there.