I had a phone call with the engineering manager. Who seemed uninterested and merely checked off boxes before shipping it to the actual interviewers. They said I could ask technical questions if I wanted as they were supposed to be able to answer them. However I got the impression they were annoyed when they couldn't fully answer. I got a rejection email soon after.

All the people were nice but the process was awful. Best case scenario I was told it was to be 6 interviews. Which that alone is a crazy amount. After the 5th interview I got an email rejection. The rejection is fine, it happens, but you would've thought at that point the hard conversations would've been done already as to not waste their or my time.