Territory upgrade, as long as you meet the conditions, doesn't actually take much time. In just a few days, the two sisters have cleared the entire world. Those experts from the Dragon Clan, either submitted or were directly eliminated.
Of course, some who ran faster have already escaped the Dragon Clan World, as for what will happen to them in the future, no one knows.
In short, without the support of the Dragon Clan World behind them, the Dragon Clan will no longer be a top race. Maybe their bloodlines are very advanced, but that only makes them targets.
Just as Du You thought, as soon as the Dragon Clan World was conquered, many worlds which dared not previously challenge the Dragon Clan stepped forward to fight. Perhaps these places wouldn't have attracted the Dragon Clan's attention, but the might of the Dragon Clan back then prevented them from acting recklessly. But now it's different; the Dragon Clan is the best target.