I can't help it - this sounds not that exciting.
Has the world shifted so much in the last years? I remember when I switched to Linux, many years ago, I worked through LFS (Linux from Scratch) within, say, one or two years. Back then that was kind of exciting; since then I expanded my own scripts for compiling or installing things, including versioned AppDirs, which to me are a lot more logical and elegant too. Why would I need or use uv? Does uv even support versioned AppDirs? How about multiple different glibc on the same system (hint: that works though you have to take care of how things are setup; think of an extended NixOS-like system, with guarantees).
uv seems to be hyped a lot and I still do not understand why.
You don't sound like a Python developer, that's probably the reason. When I search for "AppDirs", I only find references to what is e.g. XDG_BASE_DIRS on Linux (and others on other platforms)? Which I asuume is not what you mean. Most likely this is something particular to your environment, whatever that is.
In the Python ecosystem, uv is great for "project management" - lock files, project dependency environments ("venv"s) etc (similar to npm for js). In the Python ecosystem it's considered best practice to bundle binary dependencies with Python libraries, and then there'll be a binary distribution for each platform (os, libc).
They are probably referencing the AppImage-related AppDirs.
> AppDirs are the “source” of AppImages. When building an AppImage, a file system image is built from such a directory, to which a runtime is prepended.
https://docs.appimage.org/reference/appdir.html