Building a RAM factory is a major investment and takes a lot of time. There is a big risk that by the time you enter production the rain will have stopped in the form of reduced demand and/or algorithmic improvements that reduce the memory required to produce good results. All of the attention is on the well funded frontier labs who may be buying up RAM as much to starve out competitors as anything else while in the background there is an army of researchers all over the world who only have a handful of consumer GPU to work with.