The author deliberately stated that the "lowered bar" only goes insofar as reducing the rate at which qualified and diverse candidates are rejected. Disregarding the words that the author intentionally wrote - likely to prevent the interpretation that underqualified candidates are accepted - is a significant disservice, in my view.
To better illustrate what it means to reduce the false negative rate without admitting underqualified candidates, consider the following scenario:
* Phone interviews have a 50% false negative rate.
* On-site interviews have a 0% false negative rate.
* Neither type of interview has a false positive rate.
* Non-diverse candidates get one phone interview, and if the interview is positive they go on to an on-site interview. If the onsite is positive, the candidate gets an offer.
* Diverse candidates get two phone interviews. If either is positive, they move on to the onsite which, if passes, gets an offer.
In this setup, no candidates are underqualified since there are no false-positives in either the phone interview or the onsite. Non-diverse candidates have a 50% false negative rate; 50% are erroneously disqualified at the phone interview stage. Diverse candidates have a 25% false negative rate. Since they go through two phone interviews, there's only a false negative if both (0.5 * 0.5 = 0.25) phone interviews are false negatives.