I emphasized the word REAL because the previous Gen4 nVme that came out were built with a modified Gen3 controller (Phison e16) hitting high temps and topping 5GBs speeds AT MOST. The ones that came out now are the first REAL Gen4 SSDs since they use brand new PciGen4 controllers built from scratch for next generation architecture, allowing speeds above 7GBs (Some say they go up to 7.4) and the temps are much more reasonable.
They use the new Samsung Alpis, the Phison 18 or the new SM controller -- The first REAL Gen4 controllers (not that modified Gen3 Phison E16). Those older modified Gen3 nVme were rushed out so AMD can say YES THERE ARE gen4 drives on the market. So the PciGen4 platform would sell more.