Why did UI's turn from practical to form over function?
E.g. Office 2003 vs Microsoft 365
It's easy to remember where everything is with a toolbar and menu bar, which allows access to any option in one click and hold move.
Seriously? Big ribbon and massive padding wasting space, as well as the ribbon being clunky to use.
Why did this happen?
Eh, I don't hate the ribbon UI. It certainly looks a lot nicer than the old ones.
I think the biggest crime is that we went towards widescreens and kept all the menus and toolbars along the top.
Another issue is complexity. In a rush to sell yearly updates, more and more features are crammed in. Most of us only use a tiny fraction of them, but there they are on the screen just in case. For everyone.
You're never going to make one UI that makes everyone happy. Most people just learn where the 20 buttons or so that they use are, and blank the rest from their mind. That's the real reason the ribbon UI got hate. Their buttons moved.