Marxism and progressivism are two different axes of political thought and action, as far as I can tell.
Some Marxists are conservative when it comes to social justice issues, while others are progressive.
I don't know how this arbitrary dichotomization of economics and politics can be countenanced, though -- 'civil society' issues have an anti-oppression political history of their own, just as the politics of class struggle and mode-of-production do, too.
As Marxists we should be explicitly *supporting* the legacy of the Civil Rights Movement (postwar U.S.), as well as the preceding U.S. Civil War, that did away with legal chattel slavery.
Social justice issues need to be *anti-oppression*, or 'progressive'. I don't see how *any* Marxist could be *for* class struggle while neglecting matters of social-minority *oppression*.
In my experience, conservative views among Marxists depends mostly on their upbringing and social context. So indigenous Marxists are extremely anti-colonialist, while white European Marxists see it as an irrelevant “identity politics” issue that detracts from class. BIPOC Marxists see racism as part and parcel of capitalist oppression, while white Marxists dismiss it as identity politics. Et cetera.
But even demographic-sectarian 'identity politics' is still itself *progressive* compared to status-quo nationalism and imperialism. Social minorities *should* be standing up for themselves on whatever identity basis, to counter ongoing cultural-colonialism efforts and financial-imperialism from the empire.
For example, Marxists have been supporting the on-the-ground efforts of Black Lives Matter and Antifa (anti-fascism), because there's no "Marxist" lifestyle-conservatism on these anti-oppression movements, albeit black-identity and anti-domestic-terrorism (single-issue), respectively.
Ideologies & Operations -- Fundamentals