A physical thing has more degree of freedom to differentiate things. Loke distance and form. So much that you can be blind and still be able to use them.
A conputer interface does not have those. You need to track the cursor and then decide how you want to move it. There’s no muscle memory. And no tactile perception. What’s left is visual differentiation and it should be slightly exaggerated.
> and it should be slightly exaggerated
The problem is that you can go too far here, and it is in fact reminding me of:
https://en.wikipedia.org/wiki/Loudness_war