A prominent open-source dev publishes their findings as to what's going on with Starfield's performance, and it's pretty darn strange.
According to Hans-Kristian Arntzen, a prominent open-source developer working on Vkd3d, a DirectX 12 to Vulkan translation layer, Starfield is not interacting properly with graphics card drivers.
Just wish they would have incorporated the fixes into the game engine at some point. I bet some of the devs would have even signed away the code for free or at least very cheap. It was annoying not being able to use mods to fix bugs in Fallout 76 that were patched in Fallout and Elder Scrolls games some as far back as Morrowind. Sure they were mostly rare like being able to get pushed into the void behind what should have been solid meshes and the game engine seeming not to care as you fall endlessly or it crashed.