Spiderman actually is a launch game, releasing Holiday 2020, that is shown at the end of the trailer. Sony confirmed PS5 is releasing Holiday 2020. GT7 had no "2020" date along with other games, which hints at a 2021+ launch window release, and would make sense considering Sony will want to spread out their first party releases. This just means PD will have more time to polish up the game. That's not a bad thing.
If you have to compare back-to-back, then it is not significant. The difference is actually minuscule comparing back-to-back. It's the same PS4 assets and quality being re-used, with spinning 2D trees that exhibit shadow LOD pop-in. Track texture detail, rocks, vegetation, NPCs are the same quality as GTSport despite the massive power difference between generations. This is just the result of PD trying to do everything in-house and not getting outsourcing help for the environment assets. It was the same issue seen with GT5 having to reuse PS2 assets, and the reason for GTSport having mixed looking tracks where stuff like Alsace look PS3 era while Nurburgring looked great despite the low track count after 4 years of development.
Meanwhile, Playground Games is the same size as Polyphony, is able to create a large variety of fully 3D vegetation that sway in the wind, and smartly used imposter 2D LOD models for the far off vegetation that eventually switch to the 3D counterpart to save on resources, all the while having voxel GI with dynamic lighting and weather, 4 different seasons each drastically changing the environment assets, and runs at a locked 60fps on One X. Polyphony will eventually get left behind again, either in quantity, or consistent quality.
Forza Horizon 4 current-gen. This isn't even photomode, it's from the drone you can fly around the whole environment in real-time.