Google Senior Software Engineer Interview Experience — Conflicting Spreadsheet Instructions and a Stressful Onsite

I interviewed for Applied AI. I don't know why a senior-level interview had only two coding rounds and one system-design round.
Questions:
Coding 1: Spreadsheet, implementing set_cell / get_cell.
Coding 2: Google Shop
System design: A customer-service system where users talk to a virtual agent and can escalate to a human.
The recruiter's feedback was that, of the three rounds, Coding 1 and system design weren't good enough. In reality, both of those rounds were terrible experiences.
Coding 1: I couldn't understand the interviewer when he spoke. He pasted the entire question, including the follow-ups, with three requirements all at once, but I couldn't tell which requirements were follow-ups, so I treated it as one question. Halfway through, he told me to do only the most basic implementation and not worry about the later requirements yet. Okay, so I wrote the most basic version and ignored the other two requirements. After I finished, he didn't tell me anything was wrong; he just kept asking me to dry-run it. I went through several dry runs, and he still said nothing. Finally, he said he'd asked me to dry-run it so I would find the problem myself. I said I hadn't found a problem. He gave me an example to dry-run, and I said, isn't that the second requirement? Didn't you tell me to do the most basic version? He said he'd told me to ignore the third one, but I needed to handle the second. There were only five minutes left in the interview. I completely lost my composure and didn't even want to keep interviewing. Even so, I quickly wrote the second part. He also said it was fine now. I still failed in the end. Actually, if he hadn't interrupted me, I would have finished all three parts together. I'd encountered a similar question just a few days earlier.
Coding 2: The interviewer didn't keep interrupting during the follow-ups and let me write it myself. I implemented all the follow-ups. No problems.
System design: The interviewer interrogated me the whole time and gave me no chance to drive the discussion myself. For every sentence I said, he asked three questions, and his attitude was terrible. It was very stressful. Still, everything was resolved in the end, and he didn't raise any objections. I don't know why I failed. Maybe it was because, during my questions at the end, I said this was the most stressful interview I'd ever had?
Anyway, interviewing really does depend on the right timing, circumstances, and people. Just knowing how to solve the problems isn't enough. But I also learned something from these Google interviews: in future interviews, if an interviewer keeps interrupting my flow, I'll just say I'll get to that, let me finish here first.