Ray tracing is where things get interesting, because it comes in two forms in Unreal Engine 5 - software-based and hardware-based. Hardware RT isn't common at all on console UE5 titles, although the classic Matrix Awakens demo does have it, which may have given the impression that it would be more widely deployed. Since then, nearly every UE5 title has shipped with the lower quality software ray tracing instead. The fact that Fortnite on Pro gets hardware RT says to me that Epic doesn't think it's a good fit for base hardware, but can be used on PS5 Pro as an easy to use upgrade. Indeed, if you check out Silent Hill 2 on Pro, hardware RT is found in the 30fps quality mode where it is absent on the standard PS5 equivalent.
In terms of the difference, RT reflections are much improved. The engine now traces against triangles that make up an object instead of the blobby signed distance fields as found in software mode. Reflected trees actually look like trees as opposed to weirdly broken up, basic approximations. SDF LODs also see pop-in with reflections, which does not happen with hardware Lumen on PS5 Pro. Everything looks stable and more consistent. The same applies to shadows from objects in reflections – they're blobby and confusing in the software mode, while the tree shadows look a lot more like the real deal in hardware mode. Moving objects like characters are added into reflections as well, which are not there with software ray tracing. The most obvious example of this is that your own player character isn't present in reflections on PS5 - but it is on Pro. Other dynamic objects like moving cars and other players are also rendered in reflections with hardware RT, but not in the software version on the base console.
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