Even if they hardly change anything you're getting way better performance. Ultra speed NVMe SSD as standard in new consoles with 7GB/s read/write makes load times go away.

They will almost certainly make a native PS5 version with a higher performance profile than the back-compat PS4 version. Higher framerate, higher resolution, higher player and object quantity rendering.

Big enough improvements without needing them to improve asset quality, pretty much just bumping up in line with running the game on a high-end PC.