Well, the claims is not exactly artificial at the level of actively entertained thought. There were, within just a few generations of Confucius and Lao-Tzu, very precise philosophical arguments between the disciples of Confucius and the disciples of Lao-Tzu. Confucius's own grandson became Taoist and rejected many Confucian notions.
In practice, however, (that is, in the day-to-day lives of the Chinese people [which notion is itself a dramatic oversimplification of the ethnic and national identities, historically]) Confucian thought and Taoist thought coexisted quite peacefully in the Chinese folk religion, getting good and mixed in with a lot of other influences.
Furthermore, as philosophical systems the two are not incompatible, even at the level of conscious discourse. Confucianism and Taoism are predicated on EXTREMELY similar cosmologies: it's fair to say that both Confucius and Lao-Tzu believed the world to be eternal in both directions, they both had a notion of the universe as unfolding itself through an unidentifiable and inexpressible primitive power/force/firmament kind of thing (what Lao-Tzu called "Tao"), they both believed that individual humans were best served when operating a harmonious relationship with the world around them.
The primary difference is that Lao-Tzu believed (to slightly oversimplify) that organized society was itself a disharmonious system that, under ordinarily experienced circumstances, was not in keeping with the Tao. Thus, Lao-Tzu believed that we should strive for a state of harmony with NATURE as it is usually understood: the trees and rocks and stuff. Confucius, on the other hand, was much more concerned with the role and place of the individual in society. I don't believe he had much of an opinion on the global relationship between society and nature, and he thus thought that man, being placed in society, should strive for harmony within that society.
This difference leads to some explosive ethical differences: Taoism reeks of anarchism, whilst Confucius actively and explicitly taught conformity to authority. Both, however, recognized the values of mindfulness, non-ego, and non-attachment. Confucius even spoke about the beauty of wu-wei, an iconically Taoist idea: in the "Analects," Confucius said that the greatest Emperor of all time did nothing but sat and faced South, and thus his rule was perfect (he even actually used the words "wu wei" in that section, to my understanding).
Anyway, the point of all this is that the separation is, like all separations, not entirely clear-cut, and the two doctrines don't HAVE to be separate. The separation, however, is not "artificial," and there was real dispute between real adherents of the schools very rapidly in their development.