Have to say I agree with this.
I'm a bit aghast at people blindly relying on cameras and even the sensors for positioning. At the risk of sounding "kids today", when I passed my test rear view cameras weren't even a thing, and even ultrasonics were pretty new tech. I had to use mirrors and have spatial awareness of the extents of the vehicle! I still have to do that with cars that don't have cameras and/or parking sensors.
I will admit to being a bit blasé sometimes with looking at the screen for parking distance, but I keep catching myself and reverting back to the mirrors, etc.