Shit NPCs Say

it's not as much as being "dumb", but more of speaking in a non-native, rarely practiced language.

when you speak a language you know, but aren't very used to, you tend to use simpler, more common words, with a lot of repetition, breaking down complex ideas into smaller, simpler concepts.

"Your morality is shallow, self serving hypocricy" is a very complex phrase, with uncommon word and a clear description of an abstract idea.

also, I don't really like the idea of Orc morality being the same as humans, so they act like big, strong tribal humans that are oppressed by other races. you are trying to make the players empathize with them as equals, but they are not. independent of morality, they should be, and sound, different from general humans.

going a little off-topic here, I'll give my orcs as a little bit of an example.
they are a proud race, both of their strength, tribal bonds and specially their capacity to bend the land to their will. they believe the earth was created by weaker gods, and that their gods put them there to conquer, tame and dominate it. so they settle in places no one else can, like swamps, cold mountains and volcanos.

you can see that in their speech

/r/DnDBehindTheScreen Thread Parent