After I upgraded my monitor to 4k I found I needed to VSync my frame rate to 30FPS. Without capping, the framerate would fluctuate between 30 and 40, but this fluctuation causes jerkyness, and keeping it to a stable 30 produces a much smoother experience. It’s fine when looking into the distance, but when looking at closer objects, especially looking down and/or zooming in, the video is really juddery.
This wouldn’t normally bother me, but a lot of commentators (and people on this forum) have said that, as this is not a game, 30FPS is perfectly acceptable. But 60FPS feels like it should be the target framerate, not 30.