[mananaysiempre]

Yes, it’s simultaneously logical if you look at how it works and immensely strange if you don’t understand the architecture. (As has been noted all the way back to the UNIX-HATERS Handbook[1], although, pace 'DonHopkins, the NeWS Book uses the same terminology—possibly because it was written late enough to contain promises of X11/NeWS.)

[1] https://www.donhopkins.com/home/catalog/unix-haters/x-window...

[the_why_of_y]

There is nothing at all strange about the terminology. Go run ps on macOS and marvel at the "WindowServer" process. The generic architectural term is "display server".

https://en.wikipedia.org/wiki/Windowing_system#Display_serve...