The problem is by deciding that they can use "systems language" (which they dropped) because "system" means "a set of connected things or parts forming a complex whole" results in every language falling under "systems language."
Others have been using it to distinguish languages suitable for writing operating systems/drivers years before Go introduced this confusion.
When I hear "systems programmer" I think computer-to-computer. Therefore when I hear "systems language" I think computer-to-computer even absent Go's use of the term. I not be disappointed if a systems language were not appropriate for creating operating systems.
Others have been using it to distinguish languages suitable for writing operating systems/drivers years before Go introduced this confusion.