> some of your premises are flatout wrong. Especially when it comes to money: it is not the majority, but a substantial portion of undergrads in these institutions are from lower middle class or lower (economically) backgrounds.
I don't find the existence of students from middle class or lower backgrounds to be contrary to any of my premises. My point is more around the network effects. The children of the elite do attend these schools. The children of the elite are by definition already elite. Exposure to these social circles, even through something like the alumni network is a massive value proposition and massively increases ones chances of becoming an elite. If the children of the elite were to go elsewhere, the social network and value goes along with them.
This is not to say Ivy Leagues don't have other merits as undergraduate institutions, such as great staff and academics.
> The higher steps of the economic ladder are overrepresented simply because having money implies better K12 education in the US, which makes it easier to get into these schools.
It's not just K12 education, it's extracurriculars, it's SAT prep, it's high schools paying recruiters to visit campus, etc. It's a virtuous cycle. But again there are also network effects to consider. Rich and powerful families want to send their children schools with children from their socioeconomic class, so they cluster.
> And while the extracurriculars available are quite great, it is not a "daycare" and the rigors of education are very high.
My point on undergrad being akin to "daycare" is not unique to Ivy Leagues. In my experience in the US, there is a certain type of student that doesn't work a job, lives in a supervised environment (dorm), doesn't pay their own bills, doesn't cook for themselves, studies occasionally and who's main focus is fraternizing with their peers. This lifestyle is what I am comparing to daycare, and I don't believe this is uncommon esp. in places that cater to those of higher socioeconomic class.