If you have HDR monitors or high resolution screens, that need fractional scaling you’re better off with Wayland and KDE.

what is wayland

Basically, whenever an app has a GUI it wants to display, it communicates that to 'the system' with all the necessary details. After which 'the system' does the rendering and whatnot. Wayland is a protocol that defines a set of rules on how this interaction should take place. Hence, technically, it is only (the defining) part of the modern solution.

how important is it?

Very. Basically, either it or its 'predecessor'^[The term is used loosely here, because there's a very big difference between the two.] X11 is involved whenever you want to display/render anything^[Which, to be clear, happens literally all the time. Unless your display needs don't go beyond what was already available on MS-DOS*.] on desktop Linux. As X11 has been abandoned in favor of Wayland, some modern features like HDR or VRR are only found on the latter. On the other hand, I believe Wayland was never meant to offer full feature-parity with X11. Hence, some unsupported edge cases may continue to exist indefinitely. Thankfully, it has come a long way. What remains are some concerns related to accessibility AND the adjustment^[Like, how only very recently Electron got to become proper Wayland-native. Note that Xwayland is included with Wayland as a compatibility layer whenever something is not Wayland-native yet.] of the surrounding ecosystem.

Not very. X11 is still widely used and works fine. Wayland is the future, but you'll probably be fine either way.

I copied this table from here: https://www.linuxteck.com/x11-vs-wayland/

| Feature | X11 | Wayland | |

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| | Architecture | Multi-program chain (X Server + WM + Compositor) | Single unified Compositor handles everything | | Render Method | RAM multi-copy — pixels duplicated per frame | Zero-copy GPU — same buffer start to finish | | Security Model | Open trust — any app sees all input and screen | Isolated by design — apps see only their own window | | Screen Tearing | Common — vsync not guaranteed by protocol | Eliminated — compositor controls frame delivery | | HiDPI / Fractional Scaling | Inconsistent — requires per-app configuration | Per-display — clean scaling built into protocol | | Multi-Monitor HDR | Limited — retrofitted support only | Full support — designed from the ground up | | SSH Remote Display | Native — X forwarding works out of the box | Needs external tools (e.g. Xwayland, RDP) | | GUI Automation Tools | Rich ecosystem — xdotool, wmctrl, AutoKey | Limited — protocol restricts cross-app access | | Legacy App Support | Full native support | XWayland compatibility bridge | | NVIDIA Driver Support | Stable — long-established | Good — driver series 495 and above | | Battery Efficiency | Higher overhead — extra RAM copies per frame | Lower overhead — GPU buffer reuse | | Development Status | Maintenance-only since 2024 | Actively developed — expanding scope |

display manager. it'll cause issues with switching applications and rendering and such. Wayland is the direction everyone is going.

Wayland is replacing X11 at a rate where quality control isn't there.