bind backspace to 'clear selection or cancel'?

was trying to customize my settings and it looks like you can bind the ‘backspace’ key to any command except the ‘clear selection or cancel’ command? kinda frustrating when the only key binding I want is the only one that doesn’t work… I get the message that the backspace key has already been bound to another command, but when I try to bind the backspace key to another command it works fine no issues