Sure any kind of frame rate conversion makes it worse, but lots of 24fps footage has visible judder. The camera can pan fast and the frame rate is too low to show fluidly.
It’s part of the 24fps look, and film makers need to be aware and avoid it as best they can. But judder is definitely a thing at 24fps.
The shutter angle (how much of the 1/24th of a second the film/sensor is exposed for) also makes a difference. The larger it is the more motion blur you get, but it looks smoother. The lower it is the less blur in each frame, but the more obvious the judder as they’re played back.
