RAM production is highly inelastic and controlled by an oligopoly. They have little desire to increase production considering the lead time and the risk that the AI demand might be transient.

They actively prefer keeping confortable margins than competing between each other. They have already been condemned for active collusion in the past.

New actors from China could shake things up a bit but the geopolitical situation makes that complicated. The market can stay broken for a long time.

They are increasing production as fast as they can (which is not fast at all, it's more like slowly steering a huge ship towards the correct direction) because current prices are too high even when accounting for the historical oligopoly dynamics. They can easily increase their collective profits by making more.