mikazuki

At the bottom of that page the author lists some tools that can fix apps that don’t respect this.

libetc - uses a .so to reroute syscalls that try to access files in $HOME, but this hasn’t been updated since 2018 boxxy - calls the tool in a Linux namespace with bindmounts to reroute files. This seems maintained but you need to alias commands like alias aws="boxxy aws"

Every tool author should use https://xdgbasedirectoryspecification.com/

Bucatini, they are so needlessly hard to pick up for almost no gain over Spaghetti. Same for some Linguine that want to untwist from your fork and try to splatter you with sauce.