With the way consoles have moved into the PC space. This argument doesn't work as well anymore. We can scale games down to oblivion if we need to.I disagree somewhat, what you described is at best a hybrid title, a next gen featured game with current gen assets or current gen asset game with next gen features. For me a pure next gen title comprise of the vast majority of its features and assets that can not be run on a current gen console. I mean you wouldn't call all those Nvidia Gamework featured multiplatforms next gen titles would you?
Ray tracing will never be considered 'low' graphics tier anytime soon.
Keep an eye out for Halo Infinite and Forza 8 - I think these will be next generation, but will be scalable to this generation.