Although this wasn't the first time that the news of Rui having fought with a Martial Sage had spread through the world like wildfire, it was certainly the first time that so many Martial Sages of different Sage-level powerhouses swore by it.
That was what set it apart from the Sekigahara and especially the Terra incident. Those incidents had more wiggle room in so far as the people who heard of them. There was room to believe that the Sages were holding back, or at the very least, trying not to kill him. It served as cope for the Martial World to slightly rationalize these events as extraordinarily impressive, but slightly exaggerated.
This time, such a thing was impossible.
The reports highlight and emphasize how the Martial Sage was trying to kill Rui from the very first attack.