The Menu + quick access bar was good for developers but terrible for users, at least compared to the ribbon.
Ribbon is absolutely an improvement for users but is more work for the XML layout and learning how to organize it.
I'm rather convinced that Ribbon is still the best way to organize quick actions, show their shortcuts (Alt to see keyboard shortcuts), and also have enough text to describe all the buttons. But it'd be nice if it were easier to make good Ribbons.
Menu was braindead easy, albeit through ancient process of .rc files and whatnot
I'm just not sure why it has to be one or the other. Look at NeXTStep. They had a menu bar (or I guess a menu panel) and a ribbon, although that term didn't exist yet, and it was definitely not 100% there yet.
I think it's the other way around. Well organised menus can help users discover what functions are available at quick glance without having to hover each icons with the mouse to know what they do. For power users, the ribbons mean you can click directly on the function you need without having to click through menus and sub-menus.
The alternative to ribbon is not menu+ quick access, it was easily customizable toolbars where you can simply drag and drop only the buttons you need in the toolbars you need at a fraction of screen space that the ribbon wastes. And no user is ever exposed to that XML garbage only a dev could love