In my understanding, the concern is not what outside attackers can do. It is what capabilities exist under Intel's control before they are reduced to some hopef

In my understanding, the concern is not what outside attackers can do. It is what capabilities exist under Intel's control before they are reduced to some hopefully benign subset. And the understanding that we have is mostly limited to what is in flash memory, e.g. the ME's BootROM hasn't been dumped yet (as far as I am aware).