Supply and demand.

When there’s not enough of something, the price goes up. This incentivizes someone to make more of it and put it out into the market, which in turn will drive the price back down.

The problem here is that there are very few places in the world with the capability of producing these higher end electronics and practically only 3 companies in charge of this. So, if they collude together as a “triopoly”, they can artificially raise prices.

Gamers Nexus has a long documentary style video looking into the DRAM Cartel here:
https://www.youtube.com/watch?v=jVzeHTlWIDY