The switch to unreal 5 is clearly the problem, you've lost a lot of work which has caused the game to REGRESS.
But in addition to having much less content than before, the graphics suck. What's the point of upgrading to unreal 5?
We need to be patient and reasonable?
The way you run, unreal will have released unreal 6 before you've got anything playable again.
The game's release on steam is scheduled for 2040 or 2050?
I would reccommend looking at Unreal Engine 5 on YouTube (Try searching 'Unreal Engine 5' features). The amount of features UE5 has that UE4 simply CANNOT do, is immense and only growing, the amount of plugins and other features the community and developers are able to make with it is absolutely insane. You might have missed it somehow, but UE5 is one of the biggest game changers for games in a very long time.
Most games that were being developed while UE5 released were too far in to switch over, but I can assure you any game company in this position that can make use of UE5 and switch over, even if it's rocky, probably would have. It's well known just how incredible UE5 is.
Some notable features I suggest looking into if you don't believe UE5 is great are;
Nanite Virtualized Geometry, Lumen Global Illumination, World Partition system, Chaos Physics, MetaSounds, Quixel Integration, and very importantly! Improved Animation Tools. (For a game with unparalleled sex animations, it's only natural that a feature like this is key to the games future)!
As for the "graphics suck"... You probably don't meet the VRAM or System requirements, we can easily see from screenshots that the game, especially the lighting
look much better!
If you don't meet VRAM requirements, then LODs will be set to low quality automatically. Try turning down shadow and lighting settings, since these tend to be the most demanding. 'Global Illumination' for example is one that can be taxing.
Though don't worry, eventually lower end PC's will have a good chance of playing the game without texture loss, when the optimization comes around!
Remember you're playing a game well before a usual game would let you play it, no Triple-A game developers give access to games this early!
Overall, I genuinely promise this was not me white knighting for the developers, nor was it an attack at you (I know how toxic threads can be), I just wanted to clarify some things about your points that I think are very important to realize and consider! I genuinely, genuinely promise you, look at UE5's features, they are insane! Even if the switch took longer than it did, it would be ever so worth it!