DrunkonDuty
he/him
I think that’s the heart of it right there. If I’ve written a whole page worth of lore for something, the actual bit worth communicating to players is probably one to two sentences of what I wrote. The rest was more for me.
I'm also a writer of lore for my own enjoyment. Being able to cherry pick out the relevant bits for players is a talent I'm still dweveloping.
In Game of Thrones, nobody would have cared about the knowledge of Tyrion Lannister being the one who was in charge of rebuilding the sewer system if it was in an info dump in the start of the campaign. It only became important for the episode with the siege and him using the knowledge to sneak into the city.
This brings up letting players add background to their character as the game unfolds. Does it help and make sense if your PC grew up in that city and was a noble or is it a cheat of sorts to declare that your character now knows X.
Nowadays I'm using bennies for players to add these sorts of thing to their characters. But if the character already has an established background with a thing then they can usually add to it without recourse to bennies.