Hi Alvin,
Of course, opinions vary. But the Postwar Mauser Parabellum was only possible because some of the older manufacturing processes were radically changed (or dropped) as otherwise the pistol would have become too expensive for the market (see what the new Krieghoff Parabellum costs).
This meant a couple of things, including not using the horrendously expensive rust blue method, machining small parts from solid blocks of metal and other time, labour and money consuming activities
In fact, Mauser got their quality control up to a level that was never reached by the pre-war manufacturing processes. Tolerances between individual parts were so small that no pre-blue fitting was needed, except for a few tricky parts.
These guns only exist because Mauser engineers found ways to overcome the problems of the old design. They should be viewed as what they are: A postwar Mauser made gun that only shares it's heritage with the pre-1948 luger design. It's not meant to be a copy of the early luger, just a more modern version using the same concept.
Some parts were cast rather than milled and also other techniques like sintering were used as well. It made sense. Why machine a part when you can cast a version that is just as good or even better?