You are on the right track by turning autosimulation off, but your update loop still quantizes simulation time to rate that is potentially very different than your display’s refresh rate.
There are many demons at play here. after a mountain of headaches I was able to get smooth procedural animation and camera synchronized with physics almost entirely jitter-free, but calling Physics2d.simulate() during fixed update was not the thing that worked. infact the dated concept of fixed update is a major source of jitter in unity…
this thread goes in to a lot of detail about what people have tried, what works and what doesn’t: Time.deltaTime Not Constant: VSync CameraFollow and Jitter