Secret Nazi experimental plane was an epic piece of vaporware

But if they keep having production delays and overruns that keep this promising technology always 6 months out of reach until, phew, the war is over… then it was vaporware. Even if they did it before and after, this model was vaporware. Piece of vaporware, not ‘tech of vaporware’ or ‘people who only made vaporware’ - to read that that way might be missing/ accidentally changing the subject. And how could you agree if you’re on a different subject?