Sarcasm. Guys around here use ‘gentleman’ and ‘fine upstanding citizen’ interchangeably and never mean either.
Looks like you combined 2 posts!
Anyway, it’s NOT sarcasm. The way the people say it, it just flows. That’s not sarcasm. They don’t put an emphasis on the word or any such thing.
Happens all the time on the 11 news. It can be a detective, cop, or a man on the street, and he always says “I saw the gentleman pass my car....” nice and easy. No sarcasm about it. Just matter-of-fact.
Annoys the HELL out of me. Especially since the word is almost never used any more.