I believe you're in the minority there, so I won't disrespect your opinion (I actually like those kinds of things to a certain degree as well) but I also want to say one big thing:
We were doing a lot of theorizing/imagining/deducing long before the lore team decided to keep things vague. We were given a set of mostly-shaped characters, each with their own goal, and a world with plenty of mystery and history.
We had the characters, we had their goals, we could let them interact in a million different ways already.
Now, we're getting the characters, but not their goals. We can imagine them, but the problem is that anyone can imagine them. We'll never all agree on a specific point. You can come up with a brilliant theory and present it to everyone, but chances are it'll be met with a very 'meh' response, and never be confirmed in any way. This can be frustrating, since you thought it made perfect sense. But it's really only as valid as the next guy's theory. All the effort you put into creating it is pointless.
Some people might argue that art doesn't need definition. But personally, I like to be able to see the artist's point, their message in their artwork. Otherwise it's just a bunch of blobs on a piece of fabric.