Ask HN: What is the role of Product Manager?

A while ago, I was surfing twitter and noticed a video from 23 year old product manager @Meta. The video doesn't seem to reflect the true role of one such product manager. However, it has a lot of "highlight reel" material. If I were to judge by the video, I would get an idea that product managers do not much.

So what is actual role of product manager?

I am genuinely curious because I come from CS background and even getting an interview for a software engineering internship at such huge company is a pretty big deal for me. So the video felt quite out of place.

Disclaimer: Please google for the link. I do not think it is a good idea to share the link.