> out of touch

This is ironic. The vast majority of users don't know about most of these functions. They just use their mouse. Even for basic things like:

- navigating & selecting text (words, lines etc.)

- switching between windows

- opening search (like spotlight, if they use it at all...)

- opening & closing windows/tabs, saving files etc.

The list goes on. UI design is not about teaching you how to use a computer. And you certainly cannot expect users to already know.

That said. I think fixed position "back to top" buttons are terrible as well and I would put fixed position header-menus in the same category. They just add clutter and worsen the UX, even for those who almost exclusively use the mouse (as you can simply drag the scroll-bar).