https://www.protondb.com/app/1105510

It's marked as unsupported by Valve, but as others have mentioned people are successfully playing it using Proton-GE instead of stock Proton. There's plenty of guides online for installing Proton GE on Deck using ProtonUp-Qt (or Wine Cellar if you use Decky Loader) if you haven't done it before.

But the Steam Deck doesn’t use Wayland so it shouldn’t be an issue

Desktop mode doesn't yet, game mode does.

You've decided that it has to be the traditional distro package manager providing the solution - but that isn't going to happen, because those have been designed to manage a single installation of interdependent software with no distinction made between core system libraries or services and end-user applications. The solutions to the problems that come from that - which also make it extremely simple to fix issues like the one you have using a single config file - led to the development of Flatpak and Snap.

Some traditional mutable distros also ship with Flatpak + Flathub configured out of box and present them alongside and with equal importance to their own distro-specific packages - e.g. Linux Mint, PopOS, Clear Linux, CentOS, and Fedora Workstation. And Ubuntu is pushing Snap. So they're all unlikely to start putting work into enhancing their distro package managers to start providing the desktop software specific features that you want.

Yeah, packages for things like Blender and Steam do exist in most distro repositories. But they make no distinction between packages that provide software like that and packages that provide core OS services + userland (systemd, pipewire, coreutils, cups, a desktop environment, and so on). What you want requires a distinction between those things.

See SteamOS, Fedora Silverblue/Kinoite + universal-blue, openSUSE Aeon/Kalpa, Endless OS, and possibly in future Ubuntu Core Desktop as examples of modern systems (or systems in development) that make use of traditional packages as the building blocks of the base OS, and then lean on application distribution methods like Flatpak or Snap to provide desktop software. Use of the distro package manager for software like Blender is explicitly discouraged by all of these.

Distro specific fixes and configurations shouldn't be necessary as long as the OS provides what the application platform needs (desktop portals, audio server, display server, print server, message bus, etc) Flatpak doesn't even prevent distro specific repositories if it's really necessary either; Fedora ships with their own Flatpak repository in addition to Flathub.

You want better control of or isolated and relocatable end-user software installation, and it already exists - it's just not being done at the traditional package manager level, and I haven't heard about any development effort going towards changing that.

The package managers and official repos for most distros would be better thought of as lego blocks to build an OS from - they have no concept of OS and application separation, and splitting installation of an OS across multiple physical drives doesn't really make sense.

Application focused distribution methods with a clear separation from the OS like Flatpak or AppImage do support this.

AppImage - drag the .appimage wherever you want it.
Flatpak - supports system and per user installs (under home directory) by default. Additional installation directories can be configured, but I'm not sure if any of the GUIs expose this feature - so likely doesn't currently pass your bar of not needing to use the command line at all.

You might have just had bad timing - the release notes for Proton 8.0-4 mention

Fixed EA Desktop having a blank log-in window after its recent update.

It's currently a test release so should be out shortly, but if you want to use it immediately there's some info on enabling it early at https://www.gamingonlinux.com/2023/09/proton-80-4-is-now-in-testing-with-a-release-candidate/

There was a HDR hackfest earlier this year. A couple of reports from after the event if you're interested https://emersion.fr/blog/2023/hdr-hackfest-wrap-up/ + https://blogs.gnome.org/shell-dev/2023/05/04/vivid-colors-in-brno/. It also got a brief mention in the System76 blog https://blog.system76.com/post/may-flowers-spring-cosmic-showers.

So it's being worked on, and it seems all involved are trying to get it right - it sounds like gamescope on SteamOS doesn't need to worry about solving all the problems that general purpose desktop compositors will have to.

It was nearly 24 years ago, so there's more than half a decade someone could be born within following it and still be eligible to vote in this referendum.

The preamble contained more than recognition of indigenous Australians, that was only one of the points in it. Full text here https://parlinfo.aph.gov.au/parlInfo/download/legislation/bills/r900_first-reps/toc_pdf/99160B01.pdf;fileType=application%2Fpdf