> Using the XDG standard leaves you with whatever the distro decides is the correct location for these files.
This is not true. Even if the distribution sets global xdg variables (none that I've come across do) - the user can always override them.
> While their recommendation is all in the home directory, I wouldn't put it past some of these distro developers to make some crazy /var/users/{uid}/config directory
This sounds like a strawman. Are you aware of any existing distros doing this? Users don't have write access to system directories in the vast majority of distributions.
This is not true. Even if the distribution sets global xdg variables (none that I've come across do) - the user can always override them.
> While their recommendation is all in the home directory, I wouldn't put it past some of these distro developers to make some crazy /var/users/{uid}/config directory
This sounds like a strawman. Are you aware of any existing distros doing this? Users don't have write access to system directories in the vast majority of distributions.