One thing to note there is GT6 selling (relatively) poorly. Why did it do that? Because it was releasing on an old console when a new one was already out, and because of that wasn't revolutionary in any way. It was mostly just GT5 with a bit more content. Players were already moving on to PS4, and didn't want this sub-par game. Also a thing to note is Spiderman Miles Morales selling more on PS5 than it did on PS4, and there were way less PS5s back then than there will be in 2022 (or whenever) when GT7 will release.