The four cow statues, the minotaur head statue, the other statues, the shards, etc. - Lots of stuff for it to not exist, or at least not be planned for season 1. The elite that guards the lava tunnel and doesnt attack back probably has more to do with the quest than any of them realize. If you look over that discord, it is definitely being picked apart by the autists as you say. The data mined shit would have at least been interesting to see - but people have found the books, shards etc. and dont even know what they did to get them in some cases. Its just all around a good little mystery to keep some intrigue going.
I personally think the game should have way more of that type of shit. Some of which leads you to new bosses with a class-general unique, or a rare that has fixed affixes and you're just hoping for RNG to bless you with a higher item level on it, etc. I dont mean some straight on, talk to 15 NPC's and pick up bear asses. I mean if you do these events in this order, it spawns a new event somewhere in the world and that even drops a piece needed to go on etc. Leave it up to the player to figure out, not a fucking NPC that makes me roll my eyes.