My WAG is because a mouse allows control using the full range of muscles from putting your back into it to delicate fingertips and the shoulder, wrist, and elbow in between.

And that’s how our bodies are wired. Anything that requires isolating muscles will not be as kinesthetic.

I think that’s why old people tilt and shift and swing Xbox controllers…and why old people can play the Wii.

But again that’s just a wild ass guess.