So your implication is that the ratio of "competent" : "completely incompetent" for students coming from these schools is roughly... 2:100?
I know you can't possibly mean that. But your language clearly implies that ratio. The only question is why you're making such a bizarre implication.
I often find that those who are so keen on “hiring broadly” have never worked in a company that hires primarily from Podunk State
Was the original article suggesting that your company hire "primarily" from Podunk State? Or simply that you probably don't want to hire near-exclusively from the Top 5?
The key is not to focus on the schools (rather than to focus extra on state schools. Instead, develop methods for identifying talent based on its own merits, regardless of where it is or what university it went to.
Which is exactly what the original article was advocating - a "completely blind, skills-first approach". In particular, it was definitely not arguing that one should "focus extra" on state schools.