The primary cultural significance of “其余” lies in its formality and its association with a clear distinction between written language (`书面语 shūmiànyǔ`) and spoken language (`口语 kǒuyǔ`) in Chinese. Using “其余” immediately elevates the register of your language. It signals education, precision, and seriousness. In everyday conversation, using “其余” might sound a bit stiff or overly formal, as if you were reading from a textbook.
The most common point of confusion for learners is distinguishing “其余” from `剩下`, `其他`, and `别的`.