De jure discrimination of all kinds can be abolished for working-age adults under capitalism. Abolition of de jure discrimination brings the spirit of capitalism closer to the pure spirit of "Freedom, Equality, Property, and Bentham." The closer the spirit of capitalism gets to "Freedom, Equality, Property, and Bentham," the more class power the bourgeoisie enjoys. The working class lose class struggle by winning culture wars . . . on capitalist terms.
(The only de jure discriminations that cannot be abolished under capitalism probably are discrimination between individuals capable of consent and individuals incapable of it; that between convicts and "law-abiding citizens"; and that -- as long as it is based on the system of nation-states -- between citizens and non-citizens.)
Once de jure discrimination gets abolished, what happens?
1. Those old criticisms of sexism, racism, heterosexism, etc. that were aimed at attainment of equal rights become neutralized at best and become agents of capital and empire at worst.
2. Elimination of de jure discrimination does away with the material basis that united upper and lower classes and strata of each oppressed community. Now, upper classes and strata of women, Blacks, queers, etc. can move up and away from their lower-class and -strata counterparts. At the same time, women, Blacks, queers, etc. of lower classes and strata get confronted with intensification of their class exploitation that is articulated with their gender, race, sexual, and other oppressions, intensification often expressed through criminalization, most obviously in the case of Blacks, for racial oppression is more intimately intertwined with class oppression than gender, sexual, and other oppressions (because the "Black race" is a category that emerged from New World slavery and Jim Crow, thus overrepresented in the lower strata of the working class, whereas women, queers, etc. are not over- or underrepresented in any class or strata). Elimination of de jure discrimination destroys civil rights movements through their success, so women, Blacks, queers, etc. of lower classes and strata now face a more powerful capitalism, better legitimated in multicultural fashion, without the material and ideological resources for resistance that their erstwhile organic intellectual leaders supplied.
What explains working-class opposition to struggles to abolish de jure discrimination? De jure discrimination confers economic rent on those who are not discriminated against. Its abolition intensifies competition -- hence opposition to it. It's no secret that the seemingly more gender-egalitarian spirit of capitalism today has been achieved, in the case of the United States, by bringing men down as much as bringing women up.
Therefore, leftists do ourselves no favor, for instance, by forgetting the fact that families, for the working class, have been units of survival in the face of, and sometimes resistance to, capital as well as sites of gender, sexual, and other oppressions. Atomization that destroys families destroys them as units of resistance as well as sites of oppressions. The same applies to all other units of survival which sometimes become units of resistance while being sites of oppressions at the same time: trade unions, religious organizations, political parties on the Left, formerly and actually existing socialist states, etc.
For the working class, the question is how we can win culture wars in such a way that we can make use of the advantages that victories in culture wars bring -- de jure elimination of obstacles to class unity -- while coping with disadvantages that arise from destructions of old units of working-class survival and resistance. Only by doing so can we propose an alternative to both plain and simple reaction to the atomizing power of capitalism on one hand and the new spirit of capitalism that exploits it at working-class expense on the other hand.
So far, leftists have been unable to answer this question in practice if not in theory.