I think calling all post-97 releases “Special Edition” is completely fair and logical, since they inherent that version’s “Special Edition” changes. Obviously they haven’t been called that officially, but that’s only because they’ve been referred to as something far worse and much more inaccurate - just the films.

We must remember that technically the SE were given their own release and their own name, and everything since has been a variation on those special edition releases, not the original releases. So calling them the SE isn’t terribly inaccurate (at least it is no more inaccurate than calling them nothing at all).