> Leaving aside the fact that process size is a marketing term these days

There was a youtube video where the guy used a scanning electron microscope to compare gate sizes between 14nm intel and 7nm AMD and both were basically the exact same size.

The conclusion was that the term is useful only to compare a single companies product line against other offerings in that line (eg comparing Intel's 14nm to Intel's 20nm makes sense but comparing Intel to AMD based on node size is meaningless).