[ternus]

Further to what's listed elsewhere:

A RAM chip takes several months to make, starting from an empty silicon wafer. Each chip takes 8-10 weeks to go through the process of lithography, deposition, etching, cleaning, etc. It then must be tested, which can take another couple of weeks, then packaged, before it can be sold to manufacturers. Thus, even if fab capacity were available today (it isn't), you'd still see a multi-month lag before new supply hit the market.

(This is an extraordinarily sensitive process, and disrupting it can cause you to lose the entire batch. You might have heard of cases where "wafer starts" had to be discarded due to a tsunami or power disruption - this is why.)

[bigbadfeline]

The actual reasons are monopolies, tariffs and sanctions - the unstable trade environment coupled with monopoly lobbying keep the market uncertain and unattractive for new players, at the same time, the old monopolies don't have any reason to invest in new production - their profits grow when the price on the strangled market keeps going up while they keep doing nothing at all.