You're not the smartest tool in the shed, right?
The Internal SSD is comprised of 12 individual memory components. These are separate and cheap as heck components that, standalone, are slow. Then the custom controller is what allows for 12 components to work as 1 and substantially increase transfer speeds to the 5.5GB/s raw
What you quoted is for the external SSD bay. Since there's not 12 channels but 4 and less priority levels, it will need extra transfer speeds in order to compensate for both.
So again, you're wrong, and spreading bullshit again.