Snap interview questions

I've been invited for the first round (one hour) for a Software Security Engineer position in Switzerland which consisted of a presentation of the team and its work, then 30 minutes of questions (which to my surprise were about system design, which is not common for graduate students), and then 15 minutes in a coding question. The interviewer was rather cold, not very friendly and I have not seen even one smile. So, pretty uncomfortable. The coding question was leetcode easy. I have not received any offer, the hiring team ghosted my emails asking for feedback. I've felt a lack of humain from the beggining to the end.