Actually, no. The XDG specifications are intended for desktop environments, the focus is on end users throughout the specs. System services and their locations

Actually, no. The XDG specifications are intended for desktop environments, the focus is on end users throughout the specs. System services and their locations are out of scope. The standard for filesystem layout was the Filesystem Hierarchy Standard [0], which predates the XDG by about a decade. Although Debian-before-multiarch was the distribution that most closely adhered to the FHS, it was not a Debian-only document. That being said, all my systems have /var/tmp as just a symlink to /tmp, regardless of what the FHS may have to say about it -- and it's cleaned weekly, not just on reboot. [0] https://refspecs.linuxfoundation.org/FHS_3.0/fhs/ch05s15.html https://refspecs.linuxfoundation.org/FHS_3.0/fhs/ch05s15.htm... is the current home, apparently