And if an extension point is added, it's better to add it in GIO, so
command line tools can use it.
I'm just curious. What command line tools use GIO (or even glib)?
A very rough list based on a grep of oe-core's metadata for glib-2.0 (so yes, this is GLib and not GIO): avahi, connman, network manager, bluez, neard, ofono, telepathy, desktop-file-utils, pkgconfig, vala, blktool, mc, gconf, dconf, gstreamer.
