The holy land wanted to become the Federation's overlord. This was something everyone knew.
The Wei clan of the holy land had a relationship with the Monster Cult and even conspired with each other. It was undoubtedly a difficult thing for the Federation to accept.
The Federation and the Monster Cult were mortal enemies, and the Wei clan's relationship with the Monster Cult tarnished the Wei clan's reputation within the Federation.
Initially, when the holy land wanted to take over the Federation, although many people hated it, even more, did not care. After all, there were already many clans and sects throughout the Federation, so why would few more matter?
However, conspiring with the Monster Cult was something the Federation could not accept.