Julia has made symbol input manageable and lets you define infix operators for many of the Unicode symbols that make sense for that. [1] And JuliaMono was designed to support the symbols that Julia does. [2]
I generally do quite fine with my Compose Key configuration, though (even on Windows, where I use WinCompose). [3]
[1]: https://docs.julialang.org/en/v1/manual/unicode-input/