I'd honestly never thought about that before!
I like the rude robots idea, but you gotta flesh it out more! Can the people get what they need by sucking up to the computers? Can they get what they need by standing up to the computers? Inquiring minds want to know!
Okay, I have one, but I don't think vault-tec has the technology. The vault is equipped with a supercomputer that constantly analyzes people's blood pressure, facial micro-expressions, etc, and immediately buts in and tells the truth any time anyone lies, down to the children. Not just bad lies; ANY lies.
"What did you think of my dinner?"
"I thought it was great, honey!"
"ALGORITHMS INDICATE THAT SUBJECT ACTUALLY FOUND IT DISGUSTING"
"I'm gonna do it, I'm gonna go for the position of Overseer's Assistant!"
"You're gonna do great, babe, you deserve it!"
"ALGORITHMS INDICATE YOUR PARTNER ACTUALLY DOES NOT BELIEVE YOU DESERVE IT AND YOU WILL NOT DO GREAT"
Man, could people even have relationships if they couldn't tell each other white lies? Or would we just be animals?