The graphic at 13:25 re current (2019) PC hardware is interesting:

  * Bus between CPU and South Bridge not protected.
    * Most of Intel's "secure boot" functionally implemented
      in South Bridge.
    * At boot time, CPU asks South Bridge ... whether it needs
      to secure boot.
  * TPM chip connected to CPU through insecure LPC bus. Any TPM
    measurement can be forged.

Maybe they meant 'current' when the Xbox One was being designed?

Edit: at about 40:30 they say, 'a lot of this is still true'.