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.
It would be nice but someone would have to rip them out of existing products and put them into new ones. Theoretically possible as a (probably fairly janky) one-off product but unlikely. Still, similar products have been made.