The check in _ke_is_excluded, which causes GKqueueFileMonitor to
fallback to GPollFileMonitor when it returns TRUE, was made to prevent
file monitor from blocking unmount of removable drives on systems not
supporting O_EVTONLY flag in open. However, since g_mount_can_unmount
always returns TRUE on Unix-like platforms, the check always returns
TRUE on non-standard mount points, which is very likely to cause all
programs on the desktop to use the polling fallback if GNOME is
installed in a different prefix for development. This makes the desktop
sluggish and results in bad developer experience on *BSD.