At this point, it's semantics. In France there is a thing called PACS [1], which is kind of what you refer to.
However to make that equivalently semantic "government version" union would require changing of a large amount of legal text (e.g. taxation legislation). If the "government version" was simply a stand-in for "married" (i.e., reusing the variable) then what difference has been achieved even semantically?
However to make that equivalently semantic "government version" union would require changing of a large amount of legal text (e.g. taxation legislation). If the "government version" was simply a stand-in for "married" (i.e., reusing the variable) then what difference has been achieved even semantically?
[1] https://en.wikipedia.org/wiki/Civil_solidarity_pact