> the sentence "a monad is a monoid in the category of endofunctors" is pretty much impossible to represent in a script like egyptian heiroglyphics or this one

单子是自函子范畴中的幺半群

It bears remembering that spoken language existed long before written language, and written language developed as a form of encoding spoken language. Purely pictorial communication utilises a small number of large symbols that make it clear what is being conveyed from pictures alone, but the language depicted is too complex and abstracted to be purely pictorial; it uses a great number of small symbols, and you cannot understand what it is trying to convey merely by looking at it as a series of pictures. For a reader to understand what is written there would require understanding the relation of symbols to spoken language.