Gnome's own Nautilus had direct support for spatial navigation for a long time in the Gnome 2 era (including briefly on by default in something like Gnome 2.6 before complaints reversed that decision), though it was obviously a small bit underwhelming compared to Mac Classic, and lost entirely in the Gnome 2 to 3 transition.

https://people.gnome.org/~bmsmith/build/nautilus-spatial-mod...

http://www.bytebot.net/geekdocs/spatial-nautilus.html