Although that's partly true, bear in mind that not all RoTs are the same. Having a hardware vendor as the RoT is better because the manufacturer has no good way

Although that's partly true, bear in mind that not all RoTs are the same. Having a hardware vendor as the RoT is better because the manufacturer has no good way to abuse their position: you can easily firewall the hardware off from the chip vendors, or otherwise monitor that it's not phoning home, and hardware vendors have no straightforward way to access their customers machines even in the absence of CC. This isn't a meaningful thing to attempt for a cloud vendor.