I agree the loop is probably inevitable, but the conductivity of earth has
nothing to do with the loop. That part of his statement is nonsense.
I am struggling to understand what I am seeing in the photo.
View attachment 81455
A) A 200A 2-pole breaker that is independent of the rest of the panel (This is unusual to see but is probably the only way they could do the additional circuit without changing out the whole box. Some inspectors don't like this.)
B) The 200A 2-pole Main Breaker for the panel
C) A 2-pole ??A Breaker on main panel. (I can not see the amperage, but based on the wire size it must be large.)