Are Social Categories Set in Stone?

When reading Asta's book, Categories We Live By: The Construction of Sex, Gender, Race and Other Social Categories, I honestly found myself quite confused at some points, especially when reading her argument(s). To begin, Asta spoke of wanting to discuss the theory of the nature of social categories. She spoke of wanting to define certain social categories, such as the categories of "women" or "queers." However, my initial question was whether she viewed these categories as categories that people are born into or that they choose to join or even that they create. I was concerned when she stated that she wanted to essentially define these categories, as I believe that much of what we have discussed in this class is that these categories cannot be truly defined. 

Continuing onto her first chapter, it seemed to me that, according to Asta's Conferralist Framework, social categories are essentially conferred properties. Thus, I took away that this meant that they have essentially been created out of popularity. Therefore, I wonder if it would be as easy to change definitions of certain social categories. While this seems unlike, I wonder what Asta would believe as the minimum threshold of people that would have to confer with one another in order to redefine a category. Or even further, I wonder whether Asta would believe that getting rid of social categories would be possible. Essentially, I ask this because I find that much of the discord among people in our society comes from having these defined categories. Therefore, if we were to get rid of social categories, I believe that we could eliminate stereotyping and much of the hatred that comes along with it.