SFC versus Vizio is exactly what you say doesn't exist. The SFC deliberately brought a case where they don't own the copyright, and says they are harmed and here's why the court should find for them.
I assume that's because even if they aren't the original rights holder, they still have standing because they (as the public) were given rights under the GPL implicitly by anyone using the GPL, for the GPL covered items. Since they were denied those rights, they were harmed, and thus have standing.
At least that would be my "layman that finds court cases and discussions of them interesting so consumes that as entertainment fairly regularly" best guess.
