Feminists are angry because they have many reasons to be angry. For thousands of years, women have been victims of domestic violence, sexual and familial harassment and abuse, prevented from making reproductive decisions about their own bodies, and they have been subject to workplace inequalities. Women have also been discouraged to speak out and are often belittled when they do. Not too many years ago, women who spoke out were committed to insane asylums or burned at the stake.
In addition, the progress towards improving these issues has always been slow and often seems to be getting slower. It’s just not fair that women are treated as inferior creatures when compared to men.