> Custom key themes were removed because the whole concept of them was broken.
The concept was never broken on macOS. It's also implemented in a brilliantly simple and very user-accessible way, and requires very little consideration from the application developer. Between that, or having a single configuration file where one can achieve a similar result, deciding which method is better probably boils down to personal preference.
No more personal preference for me though.
> The only one anyone ever seemed to use was the Emacs theme and that just broke apps because they didn't handle the case when an Emacs binding conflicted with the app's own keys.
Again, macOS does effectively have what can be summarised as "Emacs keybindings": C-a, C-k, C-b, etc all do what you expect them to do, and if you do ever find any particular key combo conflicting for some obscure reason, you have a simple, system-level tool to fix it.
I know the issue under GNOME mostly comes from trying to find a compromise between copying what Windows does, and what's native to the terminal, but all I'm really trying to achieve is to have a consistent working environment.
The way things are: in the terminal, Ctrl-C sends an interrupt, and Ctrl-Shift-C (or some other combination, depending on your terminal emulator) copies text; in Emacs C-c is a command prefix, and M-w is copy; etcetera. I find working like this frustrating; I could probably stomach having Ctrl-C as copy everywhere (even if it meant doing something unspeakable to the terminal emulator to keep the ability to send SIGINT to the foreground process), but I used to be able to whackamole every app into respecting my preference for using Cmd-C for that. Switching between all these conventions is unnecessary mental fatigue.
I know my argument is pretty much https://xkcd.com/1172/>, but it's still quite disappointing that the "free" desktop is where my preference is disrespected.