Yes, I'm sure if your kid had majored in English at a non-Ivy school, the investment banks would still have hired him. Conversely, if your kid had majored in accounting at his Ivy, the investment banks wouldn't have been interested because he wouldn't have shown he could "think".
Prestige is a big thing for ivy grads regardless of major getting prestigious jobs, but I don't think it's all so cut and dry.
I graduated in the midst of the recession from a SLAC. A very well respected SLAC, but nowhere near as selective as an ivy, and one small enough that there are plenty of people who haven't heard from it. I also graduated in the middle of the recession. I can't speak to the job search as a humanities major myself since I studied a STEM field, however I have plenty of English, Classics, Religion, and History major friends. Some of those people went to law school, some in the T14, and some at regional schools near where they wanted to practice with scholarships. A few are employed in Big Law, and a few others are employed in smaller firms or have moved in house. Some of those people did the pre-med prerequisites with a humanities major and went to med school and are now residents. A few more went to graduate school in the humanities--they were really passionate about what they were studying and wanted to make a go of academia. Only time will tell if they regret that decision.
A few are unemployed or underemployed. But mostly, those who didn't go on to graduate or professional school are employed in normal white collar professions. A classics major friend does marketing for a publishing company. Of the English and other humanities majors I know off the top of my head, one is in marketing for some company that makes MOOCs, a couple are journalists (one has even made her way up to an editorial position), a few others work for publishing companies, a few work for think tanks and non-profits, a few work as paralegals, another does production work for some show that Hulu produces, a couple became management consultants, a few others do analyst work for banks, some went into K-12 teaching, and a few are copywriters. Not investment bankers, and often you have to start off around 30K and work your way up (although not always), but mostly people seem to be finding jobs that require a college degree. A lot of people manage websites and twitter feeds without communications theory class or some such just fine.