I was expecting an offer but they rejected me for the silliest reason

Position : Data Scientist Have been laid off since 3 months. Faced so many rejections in that time. This one company who had given a coding assessment. It was LeetCode type - 1 SQL and 2 Medium Array

Position : Data Scientist Have been laid off since 3 months. Faced so many rejections in that time. This one company who had given a coding assessment. It was LeetCode type - 1 SQL and 2 Medium Array type questions. Once the assignment was completed they had scheduled another interview for me to walk through the code and explain my solution. My solution passed 93% of the test cases. In code walkthrough I explained everything in detail and even answered all the counter questions they had. Overall feedback was very positive and I was even told by the recruiter that I am the preferred candidate. But today I learned that I was not selected. Recruiter gave me this feedback - when I was explaining my code and the interviewer suggested their approach I only acknowledged their response, but I should have spoken more about it. If I recall I had said “yes that is also a great way to approach it.” to the interviewer. I had no idea I could be rejected for this! Is this my fault? Or they are nitpicking? Usually I am not used to LeetCode type interviews for DS positions. I can’t believe they spent 3 weeks of interviews with me just to reject me for this. I was very hopeful.