IMO, it’s about being able to one-hand the phone. With the Nexus 5, though the phone wasn’t much smaller than something like my pixel 7, the bezel put the screen within reach of my thumb while holding the phone. With the 7, I have to adjust my hand or two hand the phone to reach the furthest parts of my screen.
I don’t have small hands.
6.1" is too big for my preferences. Give me a 5.5" or even a 5", and I’ll be flying.