You think this is bad? Try using Apple Music with a traditional mouse. You can’t even right click on half of the interface, dragging elements near to scrollable edges doesn’t trigger any scroll, and UI elements like the star on favourited songs just don’t show up. It’s marginally better on a trackpad.

Tried that now. I have a USB mouse. Can't say I noticed any issues? Scrolling works fine, star works fine... resizing is fine.

Using Music.app on 26.0.1