> I guess the first version of office that we all hate is the first one that came out after we were kids and learning new UI was fun.
It's not (just) that. It's that the "ribbon" didn't simplify things, it just lowered the number of clicks to get to some things. But one of the reasons you organize things in submenus is to organize things.
It's easier and faster to find a particular thing hiding within a few dozen labelled boxes, each filled with another few dozen labeled boxes, than to find something when all of the contents of all of those boxes are dumped out onto the floor. Even more, within a hierarchy it's easier to find other, closely related things to the thing that you were looking for, if the thing you were looking for turns out not to do the job.