O'Brien's character did have some anachronistic flanderization to him. The writers clearly enjoyed writing him as though he were basically their 90s uncle in the Star Trek setting... including the weird racism. It would work better if he got called out for it more from other characters, but I recall that they usually just let those comments slide.
the most unrealistic thing about o'brien is that he's somehow turned off by japanese food. he's dozens of generations removed from sushi becoming a fad. i fully expected him to complain to keiko that proper japanese food is deep fried like in his homeland of michigan, ireland.
but in all seriousness, a major subplot in that episode of TNG was about o'brien confronting the racial hatred instilled in him by the war. its not surprising that people on twitter are trying to find degrees of racism with the slurs he uses, but its still weird.
i love my futuristic wife guy and you are not going to change my opinion about him no matter what you post
Just to add to what's being said here. I always thought that a lot of the racism (despite it being worked on in later episodes - even though it was definitely still there) didn't "show" because of the inherent military nature of the federation.
If he's just taking orders and doing his job, while only making loud complaints of the garbage Cardassian computer (which ALMOST killed Dukat himself in the episode "Civil Defense"), then maybe it doesn't come out much. Like, I had NO idea O'Brien hated Cardassians so much until the TNG episode The Wounded.
I think even the show, Community, does a funny (non-Star Trek related) riff on this type of stuff in the episode "Aerodynamics of Gender." ** By "type of stuff," I mean the idea of being able to just make someone a racist after-the-fact with inserted footage, or dialogue that would otherwise not be part of the character.
The Wounded is the first time Cardassians appear in Star Trek. Their first episode is about how OBrien hates them. Also imma level with ya, the Cardassians were space nazis
