The definition of Feminism you cited in right on the money. It's the advocacy of women's rights on the basis of the equality of the sexes. Some feminists may actually care about men and their social issues, Other feminists may be apathetic towards men and dismiss their issues. Some feminists hate men outright. Feminism does not do any of these things. Feminism is an ideal while feminists are human. Feminists are typically women and being human are subject to in-group and out-group biases, just like anyone else.

If Feminism included addressing men’s inequality, I would agree that it directly benefits men, but it doesn’t. Thusly, feminists aren’t out there trying to close the educational gap. They aren’t trying to close sentencing gap between men and women. Feminists aren’t trying to address the funding gap between things like breast cancer and prostate cancer. Feminists aren’t trying to understand why there are so many homeless men relative to women. Feminists aren’t trying to understand why so many men commit suicide relative to women. Feminism doesn’t directly benefit men.

Toxic Masculinity is no longer a helpful term for helping men. It has been coopted by some feminists (not Feminism) to attack men, not help them.