Usually if you look far enough up the supply line, you find a shortage of rare elements such as lithium and cobalt iirc.
It's exactly why we are jockeying for influence in places like Afghanistan and Africa, where a) this shit gets mined and b) China beat us to the punch.
On top of which, there is an organic break point where its not financially feasible to tool up production because it costs X dollars to do so which costs more than you can recoup by the time you have to retool for next generation chips.