There are so many aspects of user interfaces that require an understanding on the interface semantics. Without that understanding, older folks just can't figure out where to go. The increased complexity logging into applications compounds the problem...2FA, captchas, pop ups the sometimes pop under.
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not only that, the interfaces are so busy and presuming what you want all the time instead of giving you straight options. i have got to a place where i am frequently wanting to just smash the thing and live without it's confusing and mentally taxing 'conveniences'.
i'm unusually skilled at working with computers, but frankly some of the interfaces these days are not made for human brains. and i say that as someone who can communicate with people in foreign languages with a bare smattering because i have also got a very good grasp of visual gestures and subtle signals indicating confusion and assumptions and other subtexts.
if you saw my keyboard you would understand that I am not incompetent at working human/machine interfaces. in fact i can design them, and they are highly efficient. just look at how much text i vomit into them.