Yes, but what would be a complete GT6?
And if GT6 is more or less "completed" but not many care because they've moved on to DriveClub or P CARS or Assetto Corsa or whatever, who is going to be happy with this if it delays GT7?
All I see in this debate is a lot of people being mad for the sake of it.
Complete GT6 is simple, once it includes everything advertised and promoted before release.
It's hardly delaying GT7, it's nobody's fault but PD that they're not done with GT6 yet. Once they are, they can fully focus on GT7. That should be how a good business operates.