People joke about it, but that's a fact, an very well known fact, since we know which tools exactly, on PC specially only one game has used DirectStorage so far because Microsoft delays and now devs late in development cycles not bring financially able to migrate (which is more than understandable, imo).
Thing is: Games take too long to make and devs won't risk even more delays because of new features players won't even miss, once cross gen period ends, that's another story, any game starting development now must implement those features so even next gen they'll be ready.