I think it is normal wear and tear.
It may have to do with the design of the bag.
The top is more structured, reinforced with more stitching, extra leather, and clasp holder. It is heavier.
If you have something like that sitting on top of one layer of leather, or a thinner layer of leather, then the weight of the top will eventually put some strain on the leather below it. (Especially if the leather is not structured or stiff like epsom, and is a softer, more malleable leather.)
I don't really think it s a "flaw", I think that will happen to many bags of similar designs.
What you can do to help prevent this, is once a while, (when not in use), stuff the bag and lay the bag flat on it's "back", with the front of the bag pointing up to the sky. That way the weight of the top from gravity will slow down the creasing.
I do this for my BV Roma bag, since the intrecciato has become very soft (and yummy) over time, but now the bag has less structure to hold itself, and the top clasp and hardware is a little heavy for it, and I don't want to pull the strips of leather too much.
My old Dior SA said the same thing for the Diorama bags when they came out. He said, if I was going to buy one, when I'm not using it or when it is in storage, may sure to stuff the bag and lay it flat on it's back facing up, because if you let it sit upright, the weight of gravity will gradually cause the bag to sort of "spread out", kind of like doing the splits (if that makes any sense).
