Duo Security Sr Software Engineer interview questions

I applied online, and was fortunate to be able to meet the hiring manager, who referred me to their recruiter. She set up a screening call right away and we had a great chat about Duo, the history of the company, the expanding offices and the new team the position was in. Very friendly and engaging. She then set up a technical interview with one of their senior engineers a few days later. The pipeline was great right up until that. The engineer conducting the interview was fifteen minutes late. The technical portion was writing solutions to simple coding challenges easily available online. The questioning was brusque and the interview was rushed and incoherent. Having conducted technical interviews for other companies, I don't understand how this process could test an engineer's skills, especially at senior level. Besides the silliness of the technical portion, the experience was great. My best to Duo and their success, and hope they continue to improve their interview process.