As per the question: the word I'm looking for is used to describe something that only one who (for want of a better way of putting it) went through something can understand that thing.
To make the question a bit less ambiguous: I went to my parents' house and they were watching a comedy which exaggerated the absurdities of the education system of Socialist eastern/central European countries during the 60s/70s. They found it hilarious because they had experienced this education system for themselves. I was scratching my head and frowning because I was brought up in a Western society in the 90s.
Consequently, my parents were watching a/an X comedy (what is X)? The word I'm not looking for is niche.
EDIT: as per below suggestions. The word should also fit the context (continuing from the above example) "I therefore find my parents' culture to be very X." The word is neither "relatable" nor "alienating" since my parents couldn't be watching an alienating comedy, but it is also not true that my parents' culture is relatable.
Perhaps it is possible that the word I'm looking for does not exist.