"Rare earths" aren't rare, they're just hard to separate and produce quite toxic & radioactive slag (they're the bottom 2 rows of the periodic table and "rare earth" mines & refineries that were operating in the US are now SuperFund sites). Due to CEOs offshoring work, most of the refining is now done in China. And the Chinese don't want to keep exporting the bare metals, they want to export the things made from those metals - like motors and electric cars made from those motors.

And the "memory shortage" is a byproduct of the AI datacenter bubble. Which is a disaster that will crash the economy.