I agree. Looking back at my comment, I did phrase it in a way that made it sound like "the company has no choice but to do this"; that wasn't my intention.
Discrimination on the basis of the school you attended, your nationality/race/ethnicity, even what you choose to do in your free time, is likely to be behind more than a few rejections. "Culture fit" is a polite fig leaf to hide that.
If the feedback can be interpreted in such a way ....
then the rejection is discriminatory.
Pure and simple.
"Culture fit" reasons are code for bias.
"Culture":
* national origin
* age
* religion
* gender
* sexual orientation....
... all protected classes, yet covered with the "culture fit" excuse to protect a company from being accused (correctly) of discrimination.