Yep, a lot of us lose some pupil expansion as we get older, so the 7mm exit pupil on the 6x42 doesn't help as much.

However, larger objective lenses do provide a sharper image, regardless of our own pupil's size, though the difference between 36mm and 42mm isn't vast. This optical principle is most noticeable in binoculars, especially 10 powers.

“Montana seems to me to be what a small boy would think Texas is like from hearing Texans.”
John Steinbeck