Well, if you use something like 0.006" wire for N scale grab-irons, they will look realistic. That's true. Paint matchign is another story. But if weathered, the color mismatch will be well camouflaged.
I was thinking more of all those factory made models where they use separate injection-molded ladders. Even though they are fairly fine in cross-section, they still look clunky, compared to the real ones. But if done properly, the molded-on ladders look more realistic than the separate plastic parts tacked onto the car. Your car and photography shows that rather nicely.