Abnormal AI Software Engineer II interview questions

The interview process was quite extensive. It began with a take-home assignment to build a file-upload application with deduplication and search functionality, which I completed and submitted. They was accepted my solution and passed me along to review round. This is where I was rejected. They asked me to describe my architectural decision and how I used AI in my design and development. The guy was impressed and then he asked me to add a feature in the take home to be able to search the content of the file? I mentioned the solution due to spending too much time in dicussion. I didn't have enough time to implement it.