Performance and visual bugs during abyss overrun

I apologize in advance for starting this way, but is devs optimzing their game a crime against humanity nowadays? Just look at this(screenshots and videos linked further down). This was unplayable, I couldn't even move further because fps would go even lower and cpu frametimes jumps to over 0.1s, to about 112ms. Monsters and my primates are almost all T-posing(watch first video). Do all dead bodies really need to be forever there, never de-spawning? This was my 4th map after starting the game. Finally decided to go back to base and alt+f4 and restart. That finally managed to bring that scene to a playable 25-30fps at least. Running around where there aren't masses of dead mobs I get about 75-90fps. Sadly the issue came back when I went further in the map. It keeps trying to load shaders after having already loaded them. When in the middle of the dead mobs, their bodies keep flashing between textured and no texture so basically almost the whole screen is flickering, reloading shaders time and time again. In the some of the screenshots mobs are on the floor, but if I move on step closer, they T-pose. Overrun is very cursed. When mobs start spawning I have to adapt to playing in 15fps, sometimes even less. I've tried hosting gold runs on juiced overrun abyss, 10-15 fps, impossible.

https://imgur.com/a/cEx0H1m
https://youtu.be/-aOaJ-MXP08
https://youtu.be/5sSQpv9XTPI
https://youtu.be/2vDoiRxmvBc
https://youtu.be/cJye9qq8hSo
https://youtu.be/qvIWk2q6F4c

Started using Profanity 2 to consume the corpses so that they don’t clutter the screen and tank fps anymore. Started one map, seemed to be working well, and fps didn’t tank so drastically after killing many. Then finished that map and started another one with Overrun abyss high Pack size(159%), just like the previous and all the other one ones, and the performance got even worse. Some of the corpses that should be consumed and disappear are still left on screen after being consumed, thus invalidating my solution. This also seems to have cause some kind of memory leak while the shaders are flickering, making the game take up to 11gb of ram (out of the 16gb that I have, normally take 6-7gb). Game kept running in 10-15fps max even when mobs were all dead and corpses consumed. Ran a few more maps, performance seemed to keep deteriorating. Flickering textures for abyss related stuff, fps tanking even further. Even restarted my laptop between runs, no improvement. Deleted all possible caches, steam cache for the game, game cache from app data, no improvement after loading all the shaders, it was still loading whatever mid-fights. I stop moving, wait a few seconds and it stops loading, I move a bit, starts loading them again. Finally gave in and switched renderer again back to Dx12. So far it seems like an improvement, frames only drop to 30-35fps instead of 10-15 during abyss overrun while mobs are spawning, and compared to vulkan, is much better even after the abysses are closed.

I'm playing on a rtx3070 140W + 11800H 8C 16T 4.2ghz cpu, 16GB ram and I'm not thermal throttling, I'm always monitoring performance of gpu and cpu. The game is installed on a 2TB M.2 SSD Nothing insane but certainly not a piece of crap. I have done every possible optimization I could find for this game. Everything. Rebar, shader cache, moving shader cache to same drive, switching global and trade to unused channels, sounds channels to low, I was running on vulkan, fps limited to 90fps just so it doesn't crash every few minutes/hours (now I’m back on Dx12 so abyss overrun is actually playable). You name it, I've done it. This game is great and I love it, 1.5k hours so far, but god damn it runs like a damn slideshow if you try to do any remotely challenging and rewarding maps. Not to mention I’m beyond tired of grey smoke/mist.