I have difficulty learning how to navigate a car's satellite radio touch screen. Things like understanding that Auto has AC on even though the AC light isn't on is hard to understand. Submenus and 6 pages of FM channels are also high in cognitive load. I'm 31, so frankly, no, age doesn't directly factor into it, but I've also been trying to teach students, coworkers, my parents, other adults, and grandparents how to use computer and their interfaces better for ~20 years.

There are a lot of tactile reasons that "stalks" work for lights and wipers, or that buttons press versus rotate. Or that things that do rotate click into place.

But if age does have a factor, vision, hearing, memory, and reaction time are all typically reduced.

Interestingly, I have 2 grandmothers at this age, both at extremely different levels of cognitive and physical ability.1 has an ipad and plays bridge on it, while the other hasn't been able to use a computer for a decade.

Not OP, but it's not just the ability but its also the willingness to learn new things.