You exaggerate. He replaces bad tubes and keeps the rest. He rarely replaces resistors; old carbon resistors are very durable and some resistors should not be replaced without good reason, such as those in instruments. He aggressively replaces paper caps and lectures about exactly why these have to go rather than indulging foolish nostalgia (they turn into resistors which overloads grids which melts irreplaceable transformers while starting a house fire.) Mica caps and most ceramics are tested and left alone. And he doesn't leave the function of the device to "magic." The design and operation of the circuit is analyzed; the first thing you see after an intro usually a circuit schematic.
It is astonishing how people perceive things.