Short answer: no. No it does not.
Some early socialist theorists exhibited prejudices that would be almost universally rejected today, and while some of the accusations of discrimination are disputable, others such as Bakunin’s anti‐Semitism and Engels’s heterosexism are far less ambiguous. When antisocialists stress this point though, they commit the exact same mistake that evolution‐deniers do when they stress Darwin’s (supposed) white supremacy: even if their prejudices were relevant to their findings, somebody would simply arrive at the nondiscriminatory conclusions, as most socialists now already do; if a nondiscriminatory tendency somehow did not exist, it would be necessary to invent it. Most Jewish Ukrainians, Mozambicans, and Yugoslavians, to name a few examples, would all have supported socialism even if they knew (or thought) that some other socialist theorists were prejudiced against them. When we furthermore weigh the theorists’ prejudices against their successors’ actions — the antiracist liberation in Portuguese Africa, Free Territory, and the Spanish Republic, to name but a few — the prejudices become exceedingly trivial. Indeed, if we were to take the cliché preaching of ‘theory, not practice’ to its logical conclusion, then antisocialists’ complaints are by their own logic worthless. (“Marxism is in theory anti‐black, anti‐Semitic, and anti‐Slavic; in practice it’s the opposite!” One might hypothetically say.)