I think the worse thing here is all the subtle breakages and inconsistencies in Windows, as well as in the MS Office suite of products, constant redesigns of things that worked, adding layers upon layers of "make-up" on top that obscures functionality, etc etc.
Not the first gui.
Not the first web browser.
Not the first spreadsheet/word processor/slideshow.
Edit: I’ll give credit, NT is good kernel, and had some novel qualities.
Microsoft tried to do everything for better and worse on wildly varied commodity hardware.