Here In This Video From 13:25 He is saying that IME Isn’t Open Source in Clear Linux
Is It True?
IME is not a part of Clear Linux, but a subsystem shipped with Intel chipsets since 08. It is true that it’s not open sourced and some people speculate that it might be a backdoor.
Personally I think this concern makes some sense, but first it’s a separate issue, and second AMD also ships a similar closed source subsystem called AMD Security Technology. So although this is a very legitimate concern, we consumer currently don’t have a better alternative.
A Raspberry Pi 4 will do 
Well, that’s true, but you know it’s not as powerful as a InteL or AMD system.
Maybe it is not the best idea to post this on an Intel related forum 
On certain specific scenarios, a cluster of raspberry pi may be good enough. But this doesn’t prove raspberry to be equally capable as a workstation built on an Intel/AMD platform.