Several years ago they added like 4 new "modern" UI styles that you can choose that are more fashionable. They're definitely innovating here, though I still find I'm most productive in the older style. And the sidebar for detailed properties is a huge improvement over 90s all-menu UI. Theme editing is also more accessible than in the Microsoft versions imo.
I should say that I disagree that office 97 era ux is necessarily worse than "modern". Office 365 is barely more capable than office 97 in any way that I care about.