[imtringued]

Making memory is easy in the sense that any company that makes JEDEC compliant DDR5 can sell you their product and you can put it into your mainboard (soldered or not).

You can't do that with Intel or AMD CPUs. There is no spec. Each vendor does CPU socketing and chipsets in their own unique way.

Not to mention that your design needs to be good. For DRAM manufacturers, they just need to design one really good cell design and spam it a billion times.

The problem is that DRAM is a specialised product that has a specialized process. Your fab is a one trick pony that can't take advantage of other markets. Since you're stuck with fixed costs on a single design, you're cranking up the volume to make your money back, but everyone does that and if everyone does it, then the market is flooded with cheap memory that won't recoup the costs.

Now that AI memory is something the companies can specialise in to increase the margins, they can exit the contested market with low differentiation. If anything, they will prefer it of a single company is left doing consumer DRAM, because it is one less company in the AI memory space.