that game shows imo that crossgen was a good thing, not a bad one.
Horizon was clearly designed with the base PS4 in mind, that means that the developers needed to be extremely cautious about CPU performance and to a lesser degree GPU.
when porting it to PS5 then, they had this high performing baseline, from which they could easily improve things to make full use of the new hardware.
And with the DLC, they then could use the highly CPU optimised engine and let loose a bit.
having last gen around forced developers to actually optimise their games to such a degree, that porting them to the current gen consoles resulted in relatively great performance, and clean visuals.
and now look at current gen only games... where developers clearly didn't really think they have to make sure the CPU is actually saturated and the game isn't bombarding 2 threads with constant draw calls of insignificant little detail noone's gonna notice anyway.
Star Wars can't keep its framerate above 30fps while barely looking better than a mid last gen title and runng at lower resolutions than many Xbox One games in performance mode, while the One X would laugh at its resolution mode...
Redfall can't launch with 60fps because clearly their CPU performance doesn't allow it, while similarly complex last gen games run flawlessly at 60fps through backwards compatibility or enhanced ports, usually at higher resolutions too.
so in conclusion, I think we should have cherished Crossgen!
Crossgen forced developers to actually care about performance! it forced them to use every single thread of those dogshit Jaguar cores to the max in order to even be able to run the games... and now, now they see "oh we got a Zen2 cpu here, now we don't have to worry about CPU performance anymore!" and the results are Jedi Survivor and Redfall... and I bet it's getting worse going forward, where we will see current gen only games that barely look better than last gen games, yet run like ass.