But this argument often rests on inequality of observable outcomes.

Which would be logical evidence if - for instance - laws were selectively enforced.

This evidence is far from iron-clad, though. Especially its real meaning.

It is like seeing a red spot on a table. Is it strawberry jam? Is it blood? Is it result of someone injecting insulin? Is it the only evidence of a murder?

Yes you are echoing the GP not contesting it.

I’m not addressing the GP. The parent comment asserts that social equality has been achieved and the social justice movement (as a monolithic group) wants more than equality in opportunity, they want equality in outcomes. I’m merely saying that the initial assumption the parent makes is believed to be incorrect by the social justice movement (that equality of opportunity has been achieved).

But all opinions under the sun are available at our fingertips, so if we judge those who disagree with us by the most extreme of their similars, we’re not going to throw much light on these issues.