Back in the 90s, I had a serial cable under the carpet from my computer to my couch. My computer would access the internet over PPP and my laptop would PPP over to my computer. Then I would launch netscape and browse the web from the comfort of my couch.

I have had a couple other use cases over the years like virt-manager at work, and a graphical management tool that I made for my son's minecraft server.

Sure there were other solutions but X11 over the wire worked well.