halvar flake (Google P0 security guy) talk a bit about it in the last Black Hat Asia : https://www.youtube.com/watch?v=JCa3PBt4r-k.
Basically he says that even Google is puny (in terms of production units) in front of Intel or Samsung, and cannot ask for custom firmwares.
Hardware security is currently a shit show because of global monopolies/"oligopolies".