Can a setting be added so that users can changed Unity’s fixedTimestep property?

This post is mainly out of hopes that the Valheim Developers will see it, though maybe some modders can make this work?

Basically, Unity has a VSync rate and a Fixed Timestep (For the fixedUpdate method) setting. As I've been trying to run the game on my Steam Deck, I've gotten a bit frustrated with constant Jittering. It's a bit odd, because this happens regardless of my FPS cap.
My Deck can't reach 60fps, so I tried getting it to run smoothly at 40hz/40fps. The Jitters were still constant. Even at 60hz with a frame rate cap of 30, it'd randomly drop.

So as I fiddled with it more and went into a rabbit hole, I read about Unity having a Fixed Update function, with the timestep set to 50 by default.

So I set my refresh rate to 50hz. Surprisingly, the frame time stabilized substantially. But it still drops, likely because of hardware limitations. But the Jitters aren't nearly as bad, and it's mostly just typical drops. So setting the Framerate/display to 50, seemed to allow it to be more in sync with the FixedUpdate task, and therefor more stable.

So if we could modify the fixed timestep to match a lower refresh rate like 40hz, I think it'll go much more stable on the Deck