How old is old? While 1960s rock stars may have talked the talk, my experience is of campaigns that actually did die before they got old. Usually I was introducing new campaigns (often also implying new systems) to old players.
The only longish running campaign with some later introduction of players was the Champions game from the mid '80s. There, the genre conventions were strong enough, assuming the players understood them, that they could hit the ground running. In the case of the genre-unaware player cited above coming in later, I guess that the campaign in mid-flow had enough momentum to ride through that sort of local difficulty, whereas a newly starting one, with less player investment all round, might have foundered in favour of something more attuned to the new consensus.