I can explain the difference between X11 and Xorg with an analogy to the web and web browsers: X11 is like HTTP, Xorg is like the Chrome browser. X11 is the protocol, Xorg is software that implements that protocol.

X11 is old, it was designed back in the 1980s and includes messages for drawing lines and circles and fonts on the screen. Also, back then there were a lot of “thin clients”, computers that were basically nothing but a browser, since graphics were computationally expensive and could not be done on the client computer, graphics rendering was done server side. There are lots of messages in the protocol for handling screen updates over a computer network.

Nowadays, all personal computers are powerful enough to render their own graphics, and no one needs the display server to draw individual lines or circles on screen. Vector graphics and fonts are done at the application level, not over the network. So these these messages specified in the X11 protocol are hardly ever used. Really, most of X11 (let’s say 90% of it) is not used at all, only the parts where the keyboard and mouse are defined, and how you can allocate memory to buffer a graphic and copy that buffer to the display. But you still need to maintain the Xorg software to handle everything that X11 specifies, and this is just a waste of code, and a waste of time for the code maintainers.

So basically, they decided about 10-15 years ago that since no one uses most of X11, let’s just define a new protocol (called Wayland) that only has the parts of X11 that everyone still uses, and get rid of the 90% of it that no one ever uses. Also, the protocol design takes into account the fact that most modern computers do all of their own rendering rather than calling out to a server to render for them. Also the Wayland protocol design takes into account that a lot of computers have graphics cards for accelerated graphics rendering.

Since the Wayland protocol is much simpler, it is easier for anyone to write their own software which implements the protocol, these software are called “compositors.” Finally, 10 years after some of the first implementations of Wayland, the protocol and compositors are becoming mature enough that they can be used in ordinary consumer PCs.

At the very beginning in early 90’s Linux adopted X11 implementation that was XFree86. It was obvious and pragmatic move, because Linux was UNIX clone with full POSIX standard compatibility, and X11 was already there for almost a decade. Porting it allowed for having graphical interface very early on (Linux started in 1991, X11 support was added one year later) and allowed all the contemporary UNIX software to be easily ported to Linux.

X11 however was designed with completely different needs in mind, as UNIX machines were mostly mainframes or powerful workstations and not home computers. It was about a lot of features that make no sense in this day and age (like network transparency, drawing primitives, printing capabilities, font rendering etc) and its design aged like milk. Xorg (that was fork of XFree86 started after license change) was implemented in a way that allows keeping compatibility for the time being with many issues being worked around and the old solution being effectively forcefully framed into modern use. It’s basically huge

Wayland started as an idea on how to do graphics on Linux (and other UNIX systems) without X, but it was never meant to be drop-in replacement. That being said, it’s vastly incompatible and the shape towards having Wayland desktops is long process of gradual implementation of new protocols to make it complete eventually.

Making Wayland possible took redesign of the OS itself. In old days, Linux didn’t think much about graphics and it was the monolithic X server that took responsibility of things like loading video drivers, setting screen modes or pushing stuff to video memory. Wayland was all about split of X’s features outside of X to gradually remove the dependency, so now the kernel has native system interfaces like kernel mode setting, direct rendering manager and so on. It’s not only Wayland taking advantage of it, as the same infrastructure is now used under X too.

Your experience wasn’t much different because it wasn’t meant to be. Desktops that are ported to Wayland are very good at abstracting things that are specific to both (otherwise completely different) display systems. You can gradually find about some things being different over time as you dive deeper.

There are certain limitations of X that Wayland doesn’t have:

• X cannot handle multiple DPI settings, so it is only possible to set one scaling factor globally for all monitors no matter their size/pixel density
• X could never properly handle multiple refresh rates for different monitors
• No way for proper HDR support on X
• VR is not really a good idea on X

On the other hand, X is very open to the user and applications, providing all sorts of information about opened windows and sniffing input globally by any client (focused or not) is a feature. In 1984 no one really thought cybersecurity will be important factor. So on Wayland:

• App can’t keylog keyboard presses or mouse movements unless its window is focused (global shortcuts are still unsolved issue, WIP)
• App can’t directly control its window position and size as it is only controlled by compositor (the idea is to introduce protocol for asking compositor on window positions relative to some area, it’s WIP)
• App cannot get image of screen or window (this is solved via PipeWire video capabilities and xdg-desktop-portal)
• Any GUI automation is compositor-specific, at least for now.

For those and other reasons (like availability of desktop environments and window managers), some still prefer Xserver.

The biggest benefits of Wayland over Xorg are to the developers maintaining it, not to the end user.

The Xorg project has become difficult to modify for new features and fixes and so they’ve decided to rewrite it.

As a result users will eventually see some benefits as Wayland implements features that were difficult to do in Xorg over time. But in the meantime it’s causing everything to be rewritten to support the new standard. And it’s a pain in the ass.

If your application works as you want on Xwayland there’s no reason to try to get it to work on Wayland native. Xwayland won’t be going away anytime soon. Eventually those applications will just switch over to Wayland and you shouldn’t need to think about it.

I can name one improvement: global scaling works SO much better in Wayland

But obviously if you don’t have a high DPI monitor, this won’t matter to you

You already understand. Wayland isn’t there yet.