Direct criticism of Guan Yu that erupted in Shu Han during his time

‌"Guan Yu relied solely on his reputation for bravery and operated the army without discipline, charging recklessly according to his own whims; thus, he lost his troops and men several times before and after."
The "fact bomb" of "Zhì yǐ yì tū ěr" (直以意突耳):
Yao Lin harshly criticized Guan Yu's military tactics as "Zhì yǐ yì tū ěr," meaning "nothing more than charging blindly according to one's own inclinations without any strategy or discipline." This is essentially describing Guan Yu, who was revered as the greatest general of his time, as a "tactless, reckless charger."
However, it wasn't just Guan Yu being criticized; Liu Bei was also harshly criticized for the Battle of Xiaoting (Yiling), resulting in him being stripped of his official positions and sent into exile.