Honestly, the reason most fantasy authors suck is cus the "evil creatures" are boring as sin with no personalities.
They give the antagonistic side NOTHING to work with and as such , they become shallow slates. Cool props for the heroes to overcome.

Speaking of which, pROTAGONISTS SUCK TOO! Not only cus most of them are teens, but they are just so..ACK. Just sick of teens. How can a teen defeat a giant beast that lived for years in the wild and is like 10x stronger. It makes no sense and makes me angry.

There are exceptions ofc, cus of storytelling skills. But more often , its just teens who got "lucky". Thats dull. Freaking dull! For once, I want a Monster to make sense. A scale. Something to ground myself. Why they live like that. Eat, sleep, talk. Something besides "rawr"!

Heroes are often idiots who just continue this cycle of "wait... you're not me!! *kills*"
People in a society which normalizes a lifestyle of xenophobia and killing foreign creatures. To which, i cant blame them, since the author made the opposition unrealistically evil!! ffs

Like, give me something to work with! Why does the Evil overlord want to kill the humans? Whats the inter politics of each race (not elves and dwarfs, not you guys). Did a big event happen which made everyone scared of eachother? Is it a big misunderstanding which grew out of pp?

No matter how much a race is "evil", a being is a being. They get scared, eat, sleep and have motivations. If all you offer to me is "they just LOVE to torture and kill cus its in their genes, what more do you want? They look evil and are evil, period.". Then you lost me.