This is repaying in kind, how Shao Changkong of Canghai Sect criticized our Yuanshan Sect, now we Yuanshan Sect, will pay it back to your Canghai Sect. So as not to make people think that Yuanshan Sect doesn't understand reciprocity.
However, Yang Chen is more subtle. He doesn't say that none of the talents of your Canghai Sect are his opponents, but instead says who can defeat me will be rewarded with Spirit Stones! Otherwise, not giving anything to those who hang around, how can anyone be crazy enough to challenge you?
If there's no challenge, how do we reclaim our reputation?
As soon as Yang Chen's voice fell, not only was the Canghai Sect surprised, but other sects also heard Yang Chen's deliberately amplified voice. Yang Chen indeed didn't intend to hide it. On the contrary, he wanted everyone to know about his challenge to the Canghai Sect's geniuses.
It's more fun for everyone to see. Otherwise, how can it be called reciprocity?