I don't see how this prevents any of that. While you are inside the running computer memory appears to you as it always has been, if you need to do post-moterm debugging you are going to need a proper crash dump anyway. This is nothing but a security benefit, it will prevent keys for full-disk crypto from remaining in memory where they can be retrieved.
If you're talking about the PSP or ME then I agree, they are dangerous and the inability to gain any insight into what they do means they should be considered hostile entities (especially if they may have access to the internal CPU memory where the encryption keys are stored).
