Exactly. I think this advice has everything to do with how far your eyeballs are from the seat of your chair, assuming good posture.

As a tall-ish person, the "standard" position for a laptop screen or old-school CRT absolutely tears my rear neck muscles up. Eyeglasses have a lot to do with this, as the focal point is dead-ahead, so I have to crane my whole noggin down to see clearly. This all creates headaches by referring pain to my scalp and, strangely, sinuses and eye sockets. I might be okay with looking down past my nose with bifocals, reading glasses, or contacts as the illustration shows, but here we are.

I'm in an in-between camp because of the above. Good posture, chin up, looking dead ahead to an elevated screen through glasses. This also works in the standing position too.