A large number of keyboard shortcuts are in conflict. "One specific keyboard shortcut has a mouse-based workaround" is not really a good answer.
The Windows GUI copied the Mac’s keyboard shortcuts (originally from Lisa?) but didn't have a dedicated key for them so re-used the existing Ctrl key, which already had a meaning on text-based operating systems. (This happened because Microsoft had no input into hardware keyboard layouts, and wanted to make software compatible with the plethora of IBM-Model-M-layout keyboards available in 1985–1990.)
Then Linux GUIs wholesale copied every feature of Windows they could including the keyboard shortcuts, in a context where this was even worse, because now existing Ctrl-based shortcuts from terminal software were directly in conflict with new Ctrl-based shortcuts from Windows.
That's why I never connect a mouse on my laptops. I've got a touchpad that's part of the keyboard. I select text with it and paste with its middle button. I only buy laptops with three physical buttons precisely because of this user case. A mouse would slow me down.
Where a mouse is really needed is in action games. A touchpad is too slow there.
Maybe, but I'm not sure about it. They are very different in location and interaction patterns.
In this context there is a lot of difference between a mouse and a touchpad. For example, I select text with the keyboard most of the times in emacs and in any other input box (not in vim, is it even possible?). So I'd lose time by reaching to a mouse. I hardly have to move my hands to use my touchpad.
The Windows GUI copied the Mac’s keyboard shortcuts (originally from Lisa?) but didn't have a dedicated key for them so re-used the existing Ctrl key, which already had a meaning on text-based operating systems. (This happened because Microsoft had no input into hardware keyboard layouts, and wanted to make software compatible with the plethora of IBM-Model-M-layout keyboards available in 1985–1990.)
Then Linux GUIs wholesale copied every feature of Windows they could including the keyboard shortcuts, in a context where this was even worse, because now existing Ctrl-based shortcuts from terminal software were directly in conflict with new Ctrl-based shortcuts from Windows.