Yep. Gotta remember that faults aren't one dimensional lines on top of the ground, but two dimensional surface planes extended into the ground.

The mostly vertical strike-slip faults in California are only about 15km deep, which limits one dimension of the fault plane to that size. The other is length. This severely limits the total area of the fault plane.

In subduction zones, not only do the faults go deeper, but also their low dip angle results in a surface area of the fault plane that is tens or more times bigger.

The energy moment released correlates to the surface area of the fault plane that slips times the amount of movement.

Brian