Japan Air Filter interview questions

Nobody was in the online meeting room despite it was already the scheduled interview time. I waited for another 10 minutes and there was still no one, so I left. 20 minutes after the scheduled interview time, the HR whatsapp me asking if I am in the meeting room. So I told him I have been there waiting for 10 minutes but no one appear. He then apologized and said they were having another urgent meeting. In my opinion, this is very unprofessional, if you are going to be late, at least you should inform me earlier. 20 minutes late to an interview, where all interviewers including HR(s) and hiring manager(s) are not able to join due to another urgent meeting? I think this is not an acceptable reason. With all due respect, an interview to me is not only me being interviewed, but also me interviewing the interviewers. I feel really disappointed at a big company for being so unprofessional and so inconsiderate.