The interview is a vibe check first and foremost. If you vibe with the team we will overlook other things in your application. If you made it to interview, we already think you're good enough so don't stress trying to impress or apologize.
Managers are mostly people who get tired of watching other people do things badly and decide to try to do better. You don't need a special degree or any magic to be a good manager, you should like people though.
The „you have to like people“ part took me nearly 20 years to figure out. I hate people in general with possible remedy for people who are nice. I‘m exceptional at managing people, I just dont vibe with them. This leads to absurd situations where everyone is happy, professionally but folks just hate my guts.
I actually am genuinely interested in that fellow's reasoning behind believing both that his job of managing people is successful, and also that all the people he managed do not like being managed by him.
Anecdotally, I have encountered workplaces containing a manager or employee that was universally disliked, and it was never because they were doing an awesome job. They did appear to think that people disliked them personally but benefited from their results. Often they seem to also believe those results would be unachievable in ways that do not produce the distaste. I am not sure these contradictions are entirely defensible.
Can confirm with a very condensed anecdote: I once applied for a job that required engineering degree in electronics or mechanics. I'm a hischool dropout. Interview went well, and I got a job offer a month later. I got the impression that they were more interested in the right type of person with relevant hands-on experience, and in my case that experience meant IT/Linux (I was always a hobbyist geek)and being used to operating heavy machinery (Grew up on a farm).
I'm still in the same industry, and I earn more than my friends with masters degrees.