Mine are not that old but they absolutely need access to assistance every day. Mom cannot turn the computer off if anything other than “Shutdown” was previously chosen in that awful Windows dialog. Dad fell for a basic “unclaimed delivery” phishing email even though he found it in the Spam folder that has an explicit warning. Fortunately, his gut told him something was fishy and he told me right away, and we suspended his card before it was abused.

What's wrong with double click?

Boy, do I understand the cringe.

I always described these users as "unable to distinguish between an icon an a button". Modern Windows UIs don't make it easier, though.