You're offering commentary, not a counterargument. What specifically is Sowell wrong about?
First, everyone here who likes Sowell can put forth specific, concrete examples where he is right, instead of making vague statements about how brilliant he is and then demanding evidence only when someone disagrees.
Why? The positive argument already exists. It's Sowell's writing. What are you asking for a cliff's notes? The disagreement you're talking about must obviously stem from something in the source material we're talking about. So what is it?
If no such evidence exists then all we have is just-so story-telling, which can be discounted.
The fact that a lot of people seem to believe his ideas are convincing is irrelevant to this discussion.
People believe all kinds of things because they sound plausible to them - partly because other people have made careers out of working out how to push people's "This sounds plausible so I shall believe it" buttons.
Which is why reproducible evidence and independent peer review are things. And why it's absolutely reasonable - in fact required - to question assertions that can't be grounded in them.
It's really just worth reading some of that stuff before you decide he's just a Tweeter. He's basically the opposite of that.