Yes, the sales have grown. A lil bit. But other than that.... nothing.
Meanwhile two years in to third gen, both Exo & Twice had already exploded & re defined the standards already.
Two years in to second gen, TVXQ were already legendary & SNSD had just exploded.
What's hindering fourth gen is the third gen imho. Mainly bts. And blackpink. Their presence is overwhelming & simply over shadowing the fourth gen. So simply it's their fault that itzy & txt sre stuck where they started.