Your first point is true, but an entirely different topic than ivy vs no-name schools. And yeah the networking benefits of top schools is absolutely their single biggest strength. See Microsoft or Apple for obvious examples. Highly capable people making a few highly capable friends, dropping out, and profiting.

This is something people just do not understand and is absolutely critical for reforming education. Elite schools do not create elite students, they enroll them. Around the pandemic numerous top schools chose to do away with standardized tests as a requirement for DEI type reasons. They're rapidly bringing them back - I know at least MIT/Dartmouth/Yale already have. And the reason is simple, which I'll quote Yale on:

"Yale’s research from before and after the pandemic has consistently demonstrated that, among all application components, test scores are the single greatest predictor of a student’s future Yale grades. This is true even after controlling for family income and other demographic variables, and it is true for subject-based exams such as AP and IB, in addition to the ACT and SAT." [1]

[1] - https://admissions.yale.edu/test-flexible