[solveit]

See also SMBC making this point a few years ago: https://www.smbc-comics.com/comic/college-level-mathematics

The problem is that being privately tutored by UC Berkeley faculty is worth much less than a UC Berkeley degree[1], even though you might learn a lot more. And starting a new university from scratch is apparently difficult, although I share your confusion on exactly which part is so difficult, and whether the difficulty could be circumvented by getting a billion or so in private donations, or if it's a case of "no matter how much money you pump into Brown, it'll never become Harvard. Only Harvard can become Harvard".

[1]: Unless you go and make yourself famous for it, which in this case might be quite doable[2]. But the general point that just learning the material without an official piece of paper recognized by the system is often worth significantly less than having the piece of paper.

[2]: And someone should do it and make headlines.