I had a laptop from work with a webcam beneath the display and hated it. Never used it as I never wanted to force people to look up my nose. When it was refresh time, the guys were telling me all about how much more RAM and processing power I was getting, all I asked was "Where's the webcam?" (It was up top, they'd fixed it.)

I think they mean literally underneath the screen, like what phone manufacturers are trying to achieve to avoid having a black dot or notch.

Not having the camera physically at the bottom of the screen (closer to the keyboard rather than at the top) like I believe the Dell XPS 13 has (or had?).

If you're at home, put your laptop on a stand (they're cheap) and then the middle of the screen is at the middle of your eye line.