On Mac, the "Super"/"Command" key controls the terminal app.
On Linux, I sometimes wish I had a Command key instead of the Control key being used by both the terminal and programs in the terminal.
On X11, "Super" is often mapped to the window manager/the desktop environment, likewise on MS-Windows where it is the Windows key.
BTW. "Hyper" is available also on Mac, by default mapped to Shift+Control+Alt+Command but it can be remapped to another key.
That key combination is emitted by the "Office key" on some Microsoft keyboards, and is used in MS-Windows for launching a component in their Office pack, or the Emoji picker.
So, there are lots of opportunities for configuration, and conflicts.
IMHO, It would be a "nice thing to have" if users could configure their text-mode programs to use more modifiers, sure ... but as long as they are the only users of that config. I don't think a text-mode program should map Super or Hyper by default.
The command key being different from the control key in macOS is really one of its biggest out-of-the-box strengths fro people who use the terminal a lot.
It's really quite helpful to have different modifier keys for different "system layers".
In addition to the Hyper key, there's also the "Meh" key, which is Shift+Control+Command and basically not used by any application. I use it as my default macro hotkey.
> On Linux, I sometimes wish I had a Command key instead of the Control key being used by both the terminal and programs in the terminal.
This is precisely why I prefer KDE — it's feasible to move GUI shortcuts off Control. (It could and should be easier, since there's a global setting deep in Qt somewhere, but it's only exposed on MacOS.)
> BTW. "Hyper" is available also on Mac, by default mapped to Shift+Control+Alt+Command but it can be remapped to another key.
I dedicate "Super" to my WM and Hyper to quite a few things but... Hyper is a hack for the USB specs do not have the concept of the Hyper key. So Hyper support is always a kludge.
BTW. "Hyper" is available also on Mac, by default mapped to Shift+Control+Alt+Command but it can be remapped to another key. That key combination is emitted by the "Office key" on some Microsoft keyboards, and is used in MS-Windows for launching a component in their Office pack, or the Emoji picker.
So, there are lots of opportunities for configuration, and conflicts. IMHO, It would be a "nice thing to have" if users could configure their text-mode programs to use more modifiers, sure ... but as long as they are the only users of that config. I don't think a text-mode program should map Super or Hyper by default.