The smart watches also struggle when used for measuring ECG or blood pressure.
That is just one aspect - older people are most hindered by the UI design in my opinion, the buttons below the fold and not obvious coz they are not visible and when they are filling some form, they just don't know what to do after filling couple of boxes.
That's just one example.
The recent development in vision LLMs show decent promise and I think we might have to augment touch with voice controls even for handled phones.
Old people won't know where the setting to turn off usb debugging is but a LLM knows and can also see things and understand, it should be able to help them.