While it wasn’t mentioned in Sony’s official announcement, developers of certain games later confirmed that PS5 exclusives like “Horizon: Forbidden West” and “Spider-Man: Miles Morales” aren’t exclusive at all. They’re both releasing PS4 versions, which may irritate a few Sony fans who took to heart Sony’s commitment to “next gen” development. The belief is that developing games across generations stifles creativity, and hampers the technological ambitions of the game, since it has to cater to an audience with less powerful machines.
“No one should be disappointed,” Ryan said. “The PS5 versions of those games are built from the ground up to take advantage of the PS5 feature set, and we have an upgrade path for PS4 users to get the PS5 versions for free. It’s about people having choice. I’m really quite pleased about the situation.”
I know for fact Spiderman was already build and you enhance the game and changed some assets but is not build from ground up for PS5.