Chaosmancer
Legend
But it isn’t lazy. It’s just not putting the explanation for every little element of the world into the narrative, which is good writing.
Tolkien didn’t ever even decide some of the unanswered questions of his work, which is to the benefit of the work.
Nonsense. Going out of his way to explain it would have been bad writing, since it would have added nothing at all to the work.
Tolkien easily could have trimmed the fat somewhere else to make room for this. There are 24 songs in the Fellowship of the Rings book alone, many of them historical in nature. There is also an entire scene devoted to the council meeting and deciding what to do, where it could have made perfect sense to include something like "Despite the great harms we have done to each other, in the First Ages of the World, we stand together to fight against the Darkness". There was no "going out of his way" when he spent so much time explaining the history of the world anyways.
Tolkien made his choice about what to include, but the fact that we are supposed to accept that all dwarves and elves are feuding, but have no idea why they are feuding was clearly a mistake on his part. I can especially say that, because it is something he tries to fix two decades later by telling that story.
And I'm not talking about "every little element" I'm talking about a massive feud between two major races of the world. This is the type of thing that defines entire nations it deserves to at least be mentioned.