It EXPLICITLY says that it does not talk about users changing things on their machines, but wants it to be something the user sets instead of a distro applying by default.
I may choose a distro that specifically looks a certain way - like the one that tries to look just like MacOS. That's a perfectly reasonable thing to want to do. Just as it's perfectly reasonable to regret consistency on a platform that doesn't have distros - as you may want to vary.
"However, if you change things like stylesheets and icons, you should be aware that you’re in unsupported territory."
Unsupported territory, for changing a desktop icon, or adding a higher or lower contrast stylesheet? Wow. That's pompous and absurd for me. Doesn't sound like it's explicitly made a reasonable exception though, just piles on a layer of entitlement for a damn brand.
If a distro is committed to modifying the style sheets to look like macOS, then it should be the distro’s responsibility to maintain the applications. Precisely because the distro market for Linux is so varied, it is hard for Gnome app developers to support all possible theme configurations.
Read the banner at the top of the page again. It doesn’t ask users to stop customizing, and it doesn’t say there shouldn’t be distros with custom theming. It just asks distros to stop shipping broken apps as a result of theming, and it asserts that if that’s the route you want to go, then you are on your own.
Choosing a Linux distro with a specific theme rather than one using Adwaita or sticking with the pre-installed Windows is the user changing things on their machine.
