I think many programming languages could benefit if we had an easy way to have both custom symbols and a convenient way to input them without extra friction. Take APL for example, once you know the language it's incredibly expressive, but the overhead to typing it is so strong that many use custom keyboards/caps.
Uiua (https://www.uiua.org/), broadly in the APL lineage, solves this problem nicely.
Like APL, it has a set of well-chosen symbols, but each symbol has an english name you can type just as you would a function name in another language, and it's automatically converted to the symbol when you run it.
To be fair the basic ASCII keyboard is also default in US/Britain. And most people assume that's all they get.
I have always used the "international" version of the US English keyboard on Linux.
And I can enter all common symbols pressing altgr or altgr-shift. I also use right Ctrl as a compose key fore more. I would be hard pressed remembering what combo to press, after years it's just muscle memory.
But how do you find out what layout and what compose key does what? Good luck. It's as documented as gesture and hidden menus on iOS and MacOS. sigh.
