Yes, that’s true, but that’s just another example of the inconsistency between the project and mixer window.
Left/right cursor can horizontal scroll in the mixer window, but not the project window.
Middle mouse button can pan (which is basically the same as scrolling) in all 4 directions in the project window, but only vertical pans in the rack section of the mixer window. Does not work at all on the fader section of the mixer window.
Shift+mouse wheel can horizontal scroll in the project window and will only scroll in the mixer window if you aren’t near the fader, pan, or rack section - which leaves a very small area that your cursor can actually be.
One simple horizontal scroll function that worked in all instances would be much easier to work with, especially given that this is a basic navigational feature. Aside from the space bar, scrolling horizontally is probably the most used function.
I actually don’t mind the shift + mousewheel function, except that it’s so easy to move a fader by mistake and then not be able to undo it.