> But terminals and editors is sticky in a way that tells me it's probably close to optimal.

Optimal for those users, at any rate. IMO using a terminal editor is so painful compared to a decent GUI (Sublime or even VSCode) that I have a difficult time understanding why anyone would choose such a tool. I just try to repeat the mantra of "everyone likes different things" and stop trying to understand something where I likely never will get it.

For me its how easy it is to extend. Kakoune makes it so easy to integrate with the rest of my system. I can often create any kind of integration I need with just 1-10 lines of code. In vscode I need to just hope that someone else built the integration I need as a plugin, because writing plugins is really painful.

Take about anything from a standard GUI editor. In a terminal editor, they are also easily accessible. And more easily accessible (if not discoverable). But one of the major gain is how close your shell is. A lot of editors allows to start a cli tool and optionally send a portion of the current buffer as input to it. You may also be able to include the output in some buffer too. Some GUI editors allows that, but it's almost always a config maze and you're never sure of the environment in which it does run the commands.

Also in a terminal environment, all you enter are keyboard keys. If you know how to touch-type, your cognitive load can be greatly reduced (personal feeling). You can also navigate something like sublime with keyboard only. But it's way more tiresome.

It’s funny. I thought the same thing before taking the time to become familiar with VIM keybindings and now I find VS Code tedious and painfully slow.

I guess once one gets used to it or anything it’s going to be more productive than the rest of the tools.