This is what I expect to happen. 2016's ram was good enough for consumers then and probably still is for a huge class of consumers now. I'd rather 32GB of DDR3 than 8gb of DDR5.
You can get like terabytes of DDR3 used. No one wants that shit. Too slow. Power hog.
DRAM rarely break, yes, I have bought cottage industry recycled DDR3 with no problem whatsoever.
The problem, however, is IO controller support has been dropped, many new CPUs don't even support DDR4 any more, especially mobile ones.