This is weird:
If you enable the “divide track list” feature, you will notice that the “unsmooth scrolling” issue is proportional to the width (height) of the window that you are scrolling.
Check this:
- enable “divide track list”
- make the height of one of the 2 track lists very small, so that you can see just 2 or 3 tracks
- try there the vertical scroll with the mouse there, it works good
You will see that the more you enlarge (height) that window, the more bad the “unsmooth scrolling” will be, it’s proportional.
I’m not a software programmer, but I feel like this could mean something…
Steinberg, please, don’t push me out to Logic after 32 years of life and work together 
, I’ve been one of your greatest ambassadors, showing hundreds of producers and programmers coming from any other software how much better is Cubase…
but this embarrassing, I can’t cover you anymore if you don’t fix it 
Cubase User since Pro-24