I speak English as a first language and I had never, in 30-something years, heard anyone refer to a room in their house as a parlour (obvs I'd read it in books, but I'm talking about real people here, in 21st Century Britain) ... until the last month when I met two unrelated people who both had parlours. Did I just randomly come across the only two people who would use this word or have I been mixing with the wrong sort of people until now? Have you got a parlour or have you got any idea how widespread their existence is?
Both people used the word to refer to a room where they wouldn't usually spend their leisure time when alone (what I would call a living room) but where they would receive guests - there were sofas and coffee tables, that kind of thing.