i believe Set represents his culture in many ways. From what I can tell Ancient Egyptian culture prized order above all else. Set gave some of them a scapegoat,and an explanation for certain mutations. He also gave them a way to justify certain forms of violence.
When the Osiris’ cult took precedence Set’s outsider status became emphasized which encouraged nationalism and the us vs.them mentality. He was partly blamed when the Hyksos took over Egypt. As god of foreigners, many believed Egypt’s failure to push them back was due to Set aiding the Hyksos.
Believe it or not, red hair and often pale skin is an extremely rare, natural mutation in Africa. Set is described as having this mutation. Because of this, those with that mutation, Egyptian or otherwise, were believed to be people of Set. People who are hot tempered were also said to be under the god’s influence.
Speaking of temper, Set was believed to represent certain kinds of violence. In Egypt, despite it’s emphasis on order, found a place for violence. That place was in combat. When you read descriptions of Pharaoh in battle you will often find references to Set and his rage. In spells and hymns you hear people ask him to destroy an enemy or evil spirits as he did protecting Ra.
It would seem that no matter how hated he was, The Egyptians were forced to recognize he was necessary for balance.