Miyazaki himself admitted he writes his stories incredibly vague on purpose. Apparently, when he was growing up he didn't speak much English but had English movies in his library. So he'd rent them and watch but could only understand bits of it. So he made the missing parts up himself.
That's how these games are made. You have an overworld and the core lore and then players have to fill the rest in, often times with conflicting theories.
Bloodborne is the only FS game I REALLY got into. And I mean really. Finished it once then watched hours of lore/theories and read fan essays on it. It has an excellent world and excellent lore. But most players wouldn't know much about it because you have to dig through theories and information obtained in interviews to piece it all together. And even then there's a lot of guesswork.
That's what I'm not a fan of. Having to go outside of the game for lore details.
Also, I have no idea how crap gets greenlit but BB still doesn't have a movie. Seriously, that thing oozes with atmosphere.