Would you consider making fish aware of a new keybindings directory inside $__fish_datadir, XDG_CONFIG_HOME, etc.?

Then, during startup, copy the user's fish_user_key_bindings function (if there is one) and create a new fish_user_key_bindings function that when invoked, will source every file in each keybindings/ directory in $__fish_datadir and XDG_CONFIG_HOME.

Basically this:

if functions -q fish_user_key_bindings
  functions -c fish_user_key_bindings __fish_user_key_bindings
end

function fish_user_key_bindings
  for file in ~/.config/fish/keybindings/*.fish
    source $file
  end
  if functions -q __fish_user_key_bindings
    __fish_user_key_bindings
  end
end

I can emulate this behavior using conf.d and distribute that script as a package, but it would be nice to have this out of the box.

In fisher v2.x (since I depend exclusively on fish autoloading feature) I go to great lengths to generate a fish_user_key_bindings function on the fly that concatenates the keybindings exported by each package with the user's key bindings defined inside their fish_user_key_bindings, but it's highly impractical (and buggy). In fisher v3.x I'll work around this more cleanly with a package as suggested above, but it would be nice if I didn't need to.

Oh-my-fish (here) and fundle (here) emulate this behavior through the user's config.fish using the same (or similar) technique described above.