Arog Pharmaceuticals interview questions

I interviewed in person with the COO after being told through email how impressed they were with my resume and application. Even though I have a PhD and many accolades, the very first question in the in-person interview was "what year did you graduate high school?" What is the purpose of asking that question other than to find out the applicant's age? I am in my 40's, so this was a red flag for obvious ageism at this company. That question is actually illegal. Extremely frustrating and disappointing.

Friendly interview with general question to get to know you and your aims. Extensive explaining about what they are expecting from the employee who will be successful and what are the company’s missions.