The above line is, of course, tongue-in-cheek, but the issue of toxicity and mutual hatred in Jacob’s family has occupied the mind of every Torah commentator. In Genesis 37:4 we see one of the expressions of this miscommunication in וַֽיִּשְׂנְא֖וּ אֹת֑וֹ וְלֹ֥א יָכְל֖וּ דַּבְּר֥וֹ לְשָׁלֹֽם׃ The hatred is so strong that the brothers are not able to communicate with Joseph peacefully.
If the hatred is already there, why then add the line about the inability to communicate? It is obvious that a hateful and spiteful person will not be able to talk with you nicely. However, everyone knows the occasions where hatred was masquerading under smooth talk and a sincere smile. The commentators here mainly state that while brothers were able to discuss the matters of business with Joseph, any filial exchange, “the peaceful conversation”, would not take place.
Rabbeinu Bahya considers this to be a positive aspect of the brothers’ characters. “Instead of hiding their hostility and flattering Joseph, they were straightforward in revealing their feelings toward him”. Bahya is a proponent of the direct communication or rather the lack of it. On second thought, this manner of speech might be preferable to the hypocritical sweet talk.