According to Duann, PC makers have to buy from SSD module makers because NAND vendors reduced allocation to the client/consumer PC market and redirected most NAND supply to data center products.
As a result, PC OEMs like Acer, Asus, Dell, and HP cannot get enough NAND or SSD supply directly from NAND manufacturers and have to turn to module makers for solid-state drives. The latter traditionally served end-users and had plenty of aftermarket products with enhanced performance and cooling, but now they increasingly serve PC makers instead.
My PC from 2019 ist now still worth more than it was when I first bought it. Thy the heck would I upgrade to someting worse for the same price? Or to something as good for a worse price?