They use the same exact chip set everybody else uses - or very, very mildly different. Plus rarely do the big corp actually design the boards. They have SuperMicro or other shops remove (mostly) unwanted parts from the otherwise standard format/layout boards. the FB and other proprietary layouts would rejigger the entire board, obviously.
These guys design SERVER boards, not piddly-ass laptop (with their rediculous contortions) / home computer boards.
Intel has chipsets without the IME but most people simply defeat the chip in BIOS or simply not place it or wire it up.
Anyway they really don't give a damn about theoretical attacks or those carried out by national actors. They are in the business of spying on YOUR workloads afterall...