That's not the case. ME code is large and not bundled inside CPU. On old systems it's was possible to not provide ME firmware while keep CPU operational.
On modern systems it's will just poweroff every 30 minutes if ME firmware not present and this is why libreboot won't support any newer hardware.
And, even worse, why is there not yet a startup competing with Intel in the desktop market?
Are fabs the issues? Knowledge? Engineers? I mean, Uber got many billions in funding, with Ubers funding one could build easily a fab for 14nm process and hire all of AMD.
On modern systems it's will just poweroff every 30 minutes if ME firmware not present and this is why libreboot won't support any newer hardware.