Lets take my Crop example. There is no way to use System Settings to add a shortcut for it because there is no menu item for it. There is a shortcut for it (c), but it is modal. I have to be in editing mode for them to work. And there don’t seem to be shortcuts to take me from mode to mode.
I have to know it is an “editing slider” (perhaps the tooltip for that icon needs a change?), and then that the first icon means crop. There is also no keyboard navigation between controls as far as I can tell, and yes I have keyboard navigation on in SystemSettings. This is an accessibility fail.
I am not even sure if the custom shortcuts app would help with most of these things. But too much of the ui has poor discoverability, I shouldn’t have to go running to the documentation to know if a feature is present. I shouldn’t have to roll over an icon to know what it means. As a disabled person, this stuff is important, and just like curb cuts they help everyone.