Resizing in the mass production line just wasn't done(other than the copper plating 1 time only).
The rough hones at the rank end did a side hone on both rod and cap to true up any mismatch in width and just the wrist-pin hole was honed to rough size. go,nogo(checked in final hone).
Final hone did the same except in much finer tolerances. if plated rods didn't meet sizing then is was scraped. It's all about the cost of the rod vs amount of labor to make the rod right.
I think resizing in the aftermarket is they take a bit off the cap or rod mating surface to make it tighter and then have to re-hone the inner bore to make a circle to spec again. The factory would never do that since it take too much time and labor, making another rod was so much cheaper to produce.