I have done my fair share of interviews. But this interviewer was simply the worst I have ever seen. Where should I start?

• The interviewer was very inattentive. He was not paying any attention. At one point, he was eating something. Usually, I would not mind, but it seemed he was doing this out of arrogance.
• He gave me a problem to solve, code perfectly, and pass all test cases within 20 minutes.
• I proposed a solution using BFS. He asked what BFS is. At first, I thought he was checking whether I knew BFS. I explained it in simple graph-theoretic terms, but it seemed he had no idea about BFS. I agreed to code the solution and then discuss.
• After I coded the solution, he still seemed confused about how it worked. At this point, I was sure he had no idea about BFS. He tried the test cases; some passed, and others timed out. Then he started talking about it not being good enough because some test cases did not pass.
• After the interview, I Googled and found that there is another DP solution available for the problem. Although it is a relatively easy problem compared to other DP problems, I then understood what happened. He had found a problem on HackerRank that required very few lines of code and was also easier to explain. In the interviewer's mind, it was a very easy problem, yet the interviewer had no idea what BFS is or how it works. Is it reasonable to give someone a DP problem to solve, code, and pass all test cases in less than 20 minutes during a phone interview?

Find the number of paths from start to end in a maze matrix. A '1' indicates that you can jump to that index, and a '0' means you cannot.