Luo Yin's "Parrots Learn to Speak": What kind of social reality do parrots reveal?

Parrot (Tang Dynasty) Luo Yin hated carving cage green feathers, while the south of the Yangtze River was warm and the west of Gansu was cold. I advise you not to make it clear, but it is difficult to make it clear.

What kind of social reality did the author of this poem reveal at that time with parrots?

By referring to the situation that the author expresses his will with the help of things, he advises parrots not to speak too clearly, but it is difficult to export what they understand, revealing the social reality that there was no freedom of speech at that time.