The concept of hijab is a complex one, and there is no single interpretation that is universally accepted. Some people believe that hijab is a requirement for all Muslim women, while others believe that it is a personal choice. There is also debate about the reasons why hijab is prescribed in Islam.
The hadith you mentioned, which is narrated by Aisha, the Prophet Muhammad's wife, does suggest that the hijab was initially intended to protect the Prophet's wives from harassment. However, it is important to note that this is just one interpretation of the hadith. Other interpretations suggest that the hijab is a way for Muslim women to express their modesty and piety.
Ultimately, the meaning of hijab is a matter of individual interpretation. There is no right or wrong answer, and each woman must decide for herself what hijab means to her.
It is also important to note that the hijab has evolved over time. The way that hijab is worn today is not necessarily the same way that it was worn in the time of the Prophet Muhammad. There is a great deal of diversity in the way that Muslim women wear hijab, and there is no single "correct" way to do it.
The important thing is that Muslim women feel comfortable and confident in the way that they dress. Hijab should not be a source of oppression or discrimination. It should be a way for women to express their faith and identity.