WELL, I'm a retired PC tech but still work whenever I'm called out to fix something or install a new PC.
Most all my customers are OLD as me or older. Weak eyes and cataracts are the norm. I even have a few folks with Macular Degeneration.
I regularly get customers who complain "my emails are in such small type, I can't read them".
When I show them how to make the type bigger, just using their mouse, they just go ape!
It's like, "WOW, GEE, That's so COOL!".
I now show that trick to all my customers, over 65 or not.
There's hardly a day goes by that I don't have to use that trick on some email, or web page.
Enjoy!