Who would not be tempted by the Great Emperor's treasure and the ancient Divine Weapons? If it were not for this restriction, the Sect Masters and Grand Elders would have wanted to enter. At that time, the conflict would be even greater, and it might even escalate into a war between the sects.
If there was a war between sects, not to mention a river of blood, the spiritual energy between the fights would make the space extremely unstable. Hence, there was such a restriction.
The major sects had agreed to send out disciples with outstanding talent and cultivation to participate. They were responsible for guarding the Primal Chaos Secret Realm to prevent the situation where those disciples could not come out if it suddenly closed.
However, the news brought back by the disciples of the Supreme Purity Sect disappointed Wu Huaqing.
"What! There's no quota for our Supreme Purity Sect? How could this be?"