So the wheel of Dharma was arficial, but at such scale and ingrained in the very fabric of the Universe that it could pass as a force of nature. The only difference is that it must be "kept spinning" by illuminated beings.
It could be either way depending on context. It's "artificial" in the sense that each individual after hearing the precious Dhamma must actively put in the real work to constantly improve upon themselves in order to make progress. But by the same token, it's also legit to say that it's also "natural" too. Like the yin-and-yang of the universe, if Samsara exists as part of the natural order of things, then the way out of it would also naturally exists. The Buddha himself certified that He did not invent anything novel all by himself. Instead He simply re-discovered the Path many of His predecessors had already discovered, and the torch will continue to be carried on long after the passing of Gotama Buddha, with the future Metteyya Buddha and others long into the future.
“Suppose, bhikkhus, a man wandering through a forest would see an ancient path, an ancient road travelled upon by people in the past. He would follow it and would see an ancient city, an ancient capital that had been inhabited by people in the past, with parks, groves, ponds, and ramparts, a delightful place. Then the man would inform the king or a royal minister: ‘Sire, know that while wandering through the forest I saw an ancient path, an ancient road travelled upon by people in the past. I followed it and saw an ancient city, an ancient capital that had been inhabited by people in the past, with parks, groves, ponds, and ramparts, a delightful place. Renovate that city, sire!’ Then the king or the royal minister would renovate the city, and some time later that city would become successful and prosperous, well populated, filled with people, attained to growth and expansion.
“So too, bhikkhus, I saw the ancient path, the ancient road travelled by the Perfectly Enlightened Ones of the past. And what is that ancient path, that ancient road? It is just this Noble Eightfold Path; that is, right view, right intention, right speech, right action, right livelihood, right effort, right mindfulness, right concentration. I followed that path and by doing so I have directly known aging-and-death, its origin, its cessation, and the way leading to its cessation. I have directly known birth … existence … clinging … .craving … feeling … contact … the six sense bases …. name-and-form … consciousness … volitional formations, their origin, their cessation, and the way leading to their cessation. Having directly known them, I have explained them to the bhikkhus, the bhikkhunīs, the male lay followers, and the female lay followers. This holy life, bhikkhus, has become successful and prosperous, extended, popular, widespread, well proclaimed among devas and humans.” ~~ SN 12.65 ~~