Yes feminism is a very important part of any struggle towards anarchism much like anarchism is a very important part of any struggle towards sex equality (or any other type of equality really).

I believe you must take on all manifestations of oppression, including the most prominent one around the globe (oppression of women), in order to create a just society. If one tackles the roots of patriarchy, they are also tackling the roots of other forms of oppression since they go hand in hand. It's not one or the other.

In the most oppressed groups of people in the world, i.e. in some southern African nations, the worst off are the women. Even if a culture is treated badly, the women of that culture are treated worse, i.e. lower-class African-American women vs. lower-class African-American men. That makes the oppression of women the most universal form of oppression in the world.

In essence, I believe that if you oppose patriarchy, sexism, and oppression of women, you are a feminist. It saddens me that some people who are for all intents and purposes feminists, do not embrace the term.

I beg you to learn a bit more about feminism before painting it with such a broad brush. You are referring specifically to liberal feminism, which certainly exists, but does not define the entire movement. Certainly anarcha-feminists like myself couldn't agree more that sexism is a symptom, not a cause, of oppression.