Just my observations:

- Editing shortcuts within the menus is not really discoverable, except by accident, it's too easy to accidentally change a shortcut that way and screw up your program, and the UI around saving/loading/resetting them is not good

- Tearoff/multicolumn menus were seen as a workaround for programs that have too many huge and/or nested menus, where something like a toolbar or a command palette would be more appropriate