Sounds like you are trying to compare the many hundreds of miles (thousands?) of transmission cables needed to cope with the massive geographic change of generation sources to this ~20mi cable system.
There are many examples of how the UK is London-centric. This isn't one of them.
It sounds like sour grapes. London contributes nearly a third of the UKs tax income. It has a higher population than the whole of Scotland.
Not to mention that over ground wires are manifestly better in every dimension except for aesthetics.
This is a great example:
https://youtu.be/z-wQnWUhX5Y?si=qdqrpJ-zS7lh2J8Z