Keep in mind that he's not interviewing every single person in the country, he's interviewing college graduates.
Not only was having a college education not as prevalent as it is now, the sole fact that the people who are taking this test have graduated from college eliminates every single one of the "discriminatory" accusations you are making. If anything, the college admissions process (an obvious prerequisite of the test) is discriminatory, not the test itself.
Adjective Making or showing an unfair or prejudicial distinction between different categories of people or things.
You may say that it is not practical to not be discriminatory. You can also say that it is not immoral to be discriminatory. Both of those may or may not be true.
However, it is certainly discriminatory to use a test that is biased towards educated white men with college degrees and access and time to read newspapers.
Those were difficult and discriminating questions at the time.
This is a time when poor girls who couldn't afford stockings wouldn't be allowed to go to school and the majority of people didn't have indoor plumbing let alone the luxury of books. Heck, 6% of possible candidates of the country were immediately eliminated because they would have not been able to read or write in any language, let alone know the arithmetic, physics, etc, required.