Everybody in my family is nearsighted and most of us also have astigmatism -- thanks Mom and Dad -- and all of us wore contacts during our teenage and young adult years. But as we got older, and particularly as we began to need reading glasses, it was just easier to give up the contacts. I suspect this may be the case for some of the royals as well as they get older. Plus glasses are easier for many people if they have problems with allergies.
I do notice that in recent photos, many of the glasses-wearing royals have opted for rimless glasses or as minimalist frames as possible. I do think such glasses are a lot less obtrusive, which may be why they are chosen.
My siblings and I all got our first glasses when >20 years old. Wondering why it wasn't noticed before we were informed that we probably had the predisposition, but it took time and circumstances to develop. My dad stated we hadden to thank our mother and her family for it. As he nor his parents and siblings hadden glasses or contacts. Except for the reading glasses when getting older. White our Mother and main part of her parents &siblings have glasses 😂
I started with contacts. But after some years I switchen to fulltime time glasses, because of laziness and especially costs. My then some years later my glasses weren't up with my eyes anyone. The frame was too old imo to put in new glasses and I hadden a very hard time to find a frame matching my facial shape. The fashion of the last years and Currently are too big for my face. As I already started with contacts for 1 day (for sportschool, holidays and such ) I switched to contacts again. And recently in coorperation with the lokal contact specialists I have now found well fitting and up to my new eye measurements contacts for a longer period of time. I have also found 1 a 2 possible frames for glasses, but wasn't 100% convinced.
A lot of people in my surroundings were contacts. The ones wearing glasses often indicate that they can't stand to be fidgling that close to their eyes or have allergies.