Menu View - New View - Rotate View
If the option of rotating Artboard is too difficult in Illustrator, maybe it is easier to create "rotated views"?
When working with packaging, the inability to rotate the view of the packaging walls while working in one document is really a prehistory of creative work. In a professional program, this must be resolved by the Adobe Customer Support Team.
Thank you everyone for the current effort.
Illustrator allows to save views, it does not matter if they are rotated or not, everything gets stored fine. The problem is that it stores everything: the rotation angle, the position of it, and the zoom level, and there is no way to control which data gets stored... and the UI / UX for it pathetic, yeah.
Still, try to use it, with View > New View / Edit Views.
Please comment back about the workflow.