I agree with some of that. Points of disagreement:
The fact that it is self-fulfilling does not make it false. And there are factors that make it not entirely self-fulfilling. If your teacher is the one who invented the concept you’re studying, there is some advantage in that, for example.
Before our present economy, 95% of students at top schools could have stable corporate law jobs if they want them. To the extent that has changed or is changing, so is salary and everything else your citations talk about. Moreover, loan repayment programs make it so loan debt is nearly irrelevant if one wants to do public interest work.
And so do many non-top schools. And many top schools have low (relatively-speaking) tuition. I haven’t run the correlation, but I really think it isn’t very strong. If the point is that top schools filter our poorer but stronger students, I see no reason to believe that. One factor you haven’t mentioned is scholarships. Perversely, the biggest scholarships tend to be offered by the best schools because they can afford it.
Not true. Again, at top schools, loan repayment programs make debt an irrelevant consideration for public interest work.