I don't know, a common issue I have seen is pointing the camera towards their face during a video call. These are people that have been taking pictures with regular cameras for decades, but give them a smartphone and they can't target their face to save their lives. They're not stupid, and I don't think it's a new concept, it's just digital instead of analogic. But a lot of older people struggle, I don't understand.
I've observed this as well. The hardest part are the basic concepts. Examples:
- The idea of a "settings menu" itself is somewhat of an alien concept and mostly limited to devices with screens.
- Not all UI elements have obvious meanings if you aren't already used to them.
- The input device itself might be unfamiliar (mouse, keyboard, touchscreen) and the user's brain might be busy trying to understand how to interact with the device at all, let alone do useful things with it.
- Some users never learned the "why" or even the "what" of existing devices, only the "how" -- they don't understand concepts like "applications", they just follow very specific steps that someone laid out for accomplishing specific tasks. This makes it very difficult to discover functionality or adapt to a different UI, because they don't know what anything actually is in the first place.