No question that Ibanking, PE, and VC are all about what school you went to. But they also represent a small share of high paying jobs, and to work in those fields, you have to live in superexpensive NYC, or maybe SF or Boston.
Moreover, top school SJs and Fs all get weeded out. Few women last more than 5 years, and SJs who like order and structure often end up in consulting and accounting. Big 4 accounting firms in NYC are filled with SJ I-banking refugees who are better off making sure spreadsheets are done accurately than advising someone on whether they should invest $150 million in another company.