Have you even listened to Dexter's internal monologue in social situations?
"What do they expect me to do now/ look happy? I think it's happy... Show some teeth."
Matt LeBlanc's character Matt leBlanc said something along these lines in his new series Episodes... "Special effects? I'm over it. You know how I was in Lost in Space, well I'll tell you a secret... I wasn't really lost in Space."
The actor pretended that the character might be feeling emotion in a funny accent.
But he's been programmed to not beleive that he has emotion, and he's been programed to reject that he has emotion even as he is experiencing emotion and exhibiting emotion...
Data should have put his foot through Rikers face for lauighing at him when he was learning to whistle.