Wonderful interview questions

I interviewed for the Deployment Strategist role in April-May. Initial round was a short conversation with HR who outlined the interview process as structured in three steps - a case study, a technical interview and final call with the CEO. The case study was fine and really enjoyable, although the interviewer at the end mentioned I'd have to go through multiple rounds instead of just a few other ones (as called out by the HR). I got the feeling the technical interview also went well, but I got a rejection email three days after without any feedback. I gently asked for a shorter feedback given the multiple rounds and was ghosted (I assume I didn't progress because I wasn't "technical" enough, although I was told I didn't need any engineer-level knowledge). Furthermore, the person I was in touch with to arrange my interviews was incredibly unresponsive throughout the process (especially when I asked to reschedule a call due to a personal emergency), at the point that I had to message one of his colleagues on LinkedIn to nudge him. Overall, not a pleasant experience