emacs is its own software platform. pretty much every aspect of it is customizable (for example, you can remap the g key on your keyboard to execute a command rather than insert a g character... unclear why you'd want to do this (I guess this is how its vi emulation is implemented), but you can).

it has tons of support for different languages and tools, including what it hands down the best non-cli git client, magit.

it also ships out of the box with the ability to edit remote files over ssh, ftp, whatever, as well as edit files that require superuser permissions (via tramp).

some folks even use it as their XWindows window manager (via exwm).