Too bad your materials engineer friend has no idea that the most hyped EV car company, Tesla, doesn't even use rare earths in its motors because they're all induction motors.

And you could of course replace the copper with the incredibly plentiful aluminum, which actually has superior conductivity per unit mass to copper. (Copper is nice because it's volumetrically more compact and is easier to make electrical connections with, but if it were seriously in danger of a shortage, none of these are anything like showstoppers to switching to aluminum.)