I feel this started a few years ago when Metamorphose released some items that aren’t considered Gothic & Lolita, including jumpsuits, their prices were quite high for what items they were offering and their sizing changed a lot, even for items in a specific series/collection (one couldn’t predict if a series would have any suitable items style and size wise). It has continued to this day, despite consistently releasing good collections (Swan Lake, Princess Crown Bouquet, etc).
At first I liked Metamorphose, their series and their simpler items, though once they started having some odd collections, I admit I went to other brands I already liked. After they started releasing more typical items again for a while, I realised I didn’t just kind of like Meta, I loved their items.
I like how they are more durable; with some other brands some of their items are delicate enough (not that is always bad) that I feel I have to be extremely careful versus Metamorphose items, even the more delicate ones, are usually (though not always) made such that one can do normal activities without worrying.
I like how they are more practical; with a lot of Metamorphose items, they stand out though not generally in a way that would alienate, since they look similar to some typical items at the same time they look unusual.
Metamorphose adds something different; lightheartedness with whimsical designs that don’t take themselves too seriously. They usually get good results with the occasional dud (see Heart Leopard series, the dresses could work if everything else being worn in plain, but the pants weren’t really useable).
One aspect Metamorphose might think of returning to is a bit of variety in their sizing; their sizing for a lot of their collections is typical instead of a small variety of differently sized items with smaller and larger sized items (I have noticed that the main larger sized items in a series are styled like their shirred pinafore dress).

See Dollpart’s post on this topic