Not a chain but a guy I work with has a well used 1980s bike that’s got its original Dura Ace 7400 chainrings and cassette still fitted and in good order as he fits a new chain a couple times a year and is meticulous about cleaning and lubing in between.
My folks have an old bike that belonged to my great, great uncle (I think). He bought it to cycle back from the pub when drink driving laws were brought in. No idea when the chain or BB were last changed, but I don't think it was in my lifetime.
Ancient chains are always a good one,
Not running anything that old myself but I bet someone on here is