It might be more accurate to say that mainstream feminists think the idea of "equity feminism" is a made up concept promoted by anti-feminists to try to devalue second- and third-wave feminism.
Sure, you can use their rhetoric if it makes you feel good. It doesn't change the fact that those mainstream feminists who call people whose beliefs align with the dictionary definition of feminism "anti-feminists" are the ones who drove women away from identifying themselves as feminists.
I wonder why they think that.