returnal unplayable on 8gb rx 7600

i have 32gb ddr5 and a ryzen 7600x as well, i dont think my specs are the issue! the game runs at a beautiful 120fps in the starter area and for a few rooms, until my vram usage fills up to ~7.7gb and the frame rate tanks to below 20fps. this happens in combat when i load a new room. ive tried proton cachyos native and the other one, also proton ge, experimental and plain old proton 9/10. nothing works!! i really want to play this game it is very fun but the lag is horrific