HH Elves work a bit different than most fantasy Elves. In HH, common elves are smaller - roughly a head on average - and they develop slower than humans do proportionally. Even though Lin has lived for 300 years, she's considered 20 years old in comparison to Humans. Because of this, their technology didn't advance as fast. The positives of living longer is that an individual can get really good at things, the negatives of a longer life span is that means less children, which means less new ideas. Elves in HH don't have magic either.
Dark Elves were extremely hard to defeat. Dark Elves are physically much stronger than humans, and they see in the dark very well. Their home is in the jungle, so they know it well. Even though their technology was shit, a good metaphor here would be Vietnam vs the US (except the US won in this metaphor). Dark Elves used spears and guerilla warfare. They covered themselves in tar and used the night and jungles to attack.
Drow were likely always going to fall to humans because they live in very small societies of 3 - 5 people in caves. They can see perfectly in the dark, but very bad in the light. They're also much stronger than even Dark Elves, but very primitive and not as smart. They likely didn't even pose much of a threat, and were just enslaved when humans got the chance.
Common Elves were hard for Humans to deal with. While their technology was still shit, they were still better than all others on the continent because they had bows and arrows. Common Elves also have an advantage in their eyes, they can see far and precisely, but up close can be blurry. Common Elves would have used the trees and vast plains, along with their bows to attack humans. But like squirrels, it was quite hard for common elves to live without using trees in various ways.
High Elves also have a trick up their sleeves. But I'm not sure I want to share it yet
Vaguely speaking, had high elves lived on the main continent they also would have been hard to defeat if they were smart and planned well. But high elves moved off the main land long before humans ever arrived.