Thanks for the suggestion. As a first step, I set it up in Nushell with a ctrl+t shortcut:

$env.config.keybindings = (
    $env.config.keybindings | append {
        name: fzf_file_picker
        modifier: control
        keycode: char_t
        mode: [emacs, vi_insert, vi_normal]
        event: {
            send: ExecuteHostCommand
            cmd: "commandline edit --insert (fzf | str trim)"
        }
    }
)

Maybe I will look into more. :) I've known about fzf but I guess never gotten around to fully evaluating and integrating it.

Nushell supports fuzzy completions, globbing, and "menus" (TUI) natively. Still, the TUI aspect and possibly other forms of integrations seem like they could be worthwhile or useful as extensions.