I don't understand why there is no such projects as mature on Linux. With access to plugins for the most used desktop environments you think it would actually be easier to implement. Running VLC borderless in the background is still the way many people suggest
That's so interesting to me, because as someone thinking about switching over to Linux after playing around with it a bit, one of my main motivations is the ability to customize the desktop like crazy. Personally I like the minimal modern look, but I like that you can make it anything you want.
It's probably more complicated precisely because of the multiple desktop environments and X11 set up. Windows you can make one tool to work on all desktops.
You'd probably need systems for KDE and Gnome, etc. Perhaps Wayland may make this simpler?
Ultimately I suspect it's just not a priority when the complexity is factored in. An animated desktop is pretty to look at but probably not a project getting lots of devs interested in if it's so complex to implement and maintain at present?
I haven't played with this too much, but I'm reasonably confident you only need an X11 and a Wayland implementation. Mplayer / mpv can play on "rootwin" on X11. For Wayland I think it's a layer.