We don’t recall, prior to mirrorless cameras causing manufacturers to redesign most of their lenses that brands would pre-announce prime lenses that weren’t very bright. Perhaps it is because Nikon is the major manufacturer furthest behind the 8-ball in terms of lens lineup rejiggering, but it felt compelled to tell everyone that new Z mount versions of a 28mm f/2.8 and a 40mm f/2 will be coming. Eventually.
They already appeared on the existing lens roadmap, but had been indicated as likely being released some time ago. This pre-announcement is likely geared to tell people that they haven’t cancelled the projects.
Nikon’s range of glass is very notable in being weighted to economy glass versus its old F-mount lineup, which ranged from economy to some of the best professional glass available. Nikon’s mirrorless bodies, when first launched, were some of the best specced bodies, but the glass has been more limiting. That contrasted with rival Canon’s first mirrorless bodies that were at best intermediate in specs, but came with bonker-class pro glass.
Canon has more than caught up on its bodies, but Nikon’s Z system has languished relatively in both bodies – recently refreshed with lackluster Mark II improvements – and release of relatively few professional-grade lenses.