But - at the risk of taking a troll's bait - perhaps we can just assume that the author of the linked blog isn't actually expecting anyone to respond to his questions literally. Instead, he's obliquely asserting that the questions he poses haven't been, and can't be, answered reasonably by people who subscribe to a "social justice" worldview. He's saying that people with that worldview are illogical or hypocritical or unreasonable, because questions like those he's raising deserve (and aren't getting) satisfactory answers.
Ultimately, the point that he's belaboring is that the "social justice" movement as he understands it doesn't rest on any fixed values, but that what's just depends on the perspective of individuals, e.g., is essentially applied moral relativism. And he's doesn't believe moral relativism is an appropriate foundation for organizing human life.
So the challenge is to either disagree, and identify fixed moral positions/values that support "social justice"; or to agree that social justice is moral relativism, but that's OK because moral relativism is OK.
Or one can say "I reject that characterization/argument" - but the danger is that others may perceive the rejection as motivated by fear or an admission of failure, especially if you don't present an alternative characterization that seems at least as reasonable.
Often, the purpose of an argument isn't to influence the other participant, but to influence others who may observe the exchange. Even if the author is "sea lioning" (aka concern trolling), if he does it effectively enough, third parties who can't tell the difference may find it convincing, and claims that "the answer is obvious" or "you should already know the answer" are unpersuasive.