ALOT of things can go wrong with your eyes, especially as we age.
Cataracts, macular degeneration, a "roughening" of the retina that means even lense replacement surgery will not get you sharp vision (fortunately not in my aiming eye
, and then there is an inner lining kind of like very thin saranwrap that can peel off and leave little black specks floating around in your vision...
Mine started out in my peripheral vision like a flock of blackbirds and have decreased with time to a swarm of gnats.
I prefer iron sights to scopes, but my iron-sighted cart. Guns have Hi Viz green front beads, incl. my HW35 pellet rifle.
My 24 ga flinter has a flat-faced silver front sight and a generously notched open rear sight mounted just behind the "wedding ring" of my oct-to-round barrel, and extremely low-mounted sights.
The rear sight means I cannot compete "for record" or prizes in a trade gun match anymore. Big deal! (Where are the rule book nazis when I have to bone a deer out in the woods since I can't even drag one more than a few feet, much less make it into a deer pack and carry it out.)
Shooting at & hitting a mark is fun, and killing your own meat mercifully & cleanly with a well-placed shot is one of several reasons to go on living.
I hunt closer, now, but I'll use whatever sights I need to to continue to "make meat" mercifully & cleanly.
Dave, aka "The Curmudgeon"