I think the reasons why China developed into an "eternal empire" while Rome didn't are much more deeply-rooted. Even before being properly united by the Qin, under the Zhou, China could still be regarded as a single cultural, political, economic unit, in a way that the Mediterranean basin region couldn't. Even during the Warring States this was partially-true. The reason for that I think is geography - it's much easier to communicate, migrate, trade, lead armies etc. through the yellow river basin, than across the Mediterranean sea. As a result, any state that held any territory in that region could easily expand or at least come into conflict with any other state that held territory in the region, until eventually one state emerged supreme, so there was an inevitability that the region of China proper would always come to be ruled by one polity. Over time this also gave legitimacy to the idea that there should be a single Chinese state, and later that there's a single Chinese nation. This means that China could never have really disintegrated into smaller polities the way Rome did. One the other hand, there was absolutely no inevitability that, for example, the Levant, Spain, and Britain would come to be ruled by the same polity. They only did eventually end up that way because of tremendous military efforts by a state with a uniquely effective army structure. So once the Roman empire in the West fell apart, it would have taken such a great effort to restore it that IMO it was highly unlikely it would ever be restored (and we've seen what happened when Justinian tried that).