How much % of the DRAM market do you think is made from computer enthusiasts upgrading their Zen 1/2 CPUs to Zen 3? Note intel and AMD both switched to DDR5 well before the exit from DDR3/DDR4 ("2024-2025", according to the complaint).
While I wouldn't necessarily agree with "a handful of people", the fact is that neither of us can prove their lean -- so no point pursuing that argument thread.
So you might be right that it's a pure numbers/statistics decision. Or I might be right that they want to herd people into the more expensive hardware while forcing them to do so by phasing out production of the cheaper hardware.
No way to truly know IMO. We are exchanging hypotheses.
DDR4 production is likely still quite profitable, just not drowning-in-money AI-bubble profitable. If smaller foundries existed they’d be happy to take up the business.
Maybe really what needs to happen is some busting up of the giants…
Otherwise they could continue to make DDR4 at a higher cost and sold at a higher price to which people will complain price fixing again.