The blogosphere suddenly became aware of the existence of Intel ME "spying at you" to paraphrase some catchy titles. If some authors seem to discover that technology, the truth is it is here for almost 10 years!
So, in order for you to make your own educated opinion, I tried to summarize the facts concerning Intel ME and the current state of the community knowledge about that technology.
Then there's this from a while back...
Deep dive into Intel Management Engine disablement
Bios level, and it wasn't truly disabled there. As with all security threats there were layers blocking it's communication, and we left it (not configured). This became less possible with later iterations of the product. But creative acling at each VLAN got the job done.
It was not easy.
@YesIKnowIT its availability and a use case of recovering crashed servers was an active selling point for many corporate grade Dell servers (and I expect a few others) about 10 years ago, although on the single big server my employers (a smaller business) could afford I have never managed to get it to work correctly anyway (and don't want to experiment on busy in production server so have shut off as much of it as I can)