I came to say something similar. Office 2000 seems more than sufficient for everybody outside of some very specific niches. The success of the comparatively much more basic Google Docs and Sheets are proof of this.
Similarly I could live happily ever after with Photoshop 7.x or CS1 if they took full advantage of modern operating systems and hardware.
I don't know, I have been forced to update many times just to use Word. Win7/Word 2003 was working fine for me as a math editor. Somehow everyone changes to .docx, Equation Editor 3.0 was replaced, then one of my major client only accept Word 2019 files for consistency so I was forced to update to Windows 10 just to use that.
And I still haven't seen an increase in productivity. In fact, migration from Equation Editor 3.0 was really painful. I could type math equations blindfolded, I know Ctrl-R for a square root, Ctrl-F for fractions, Ctrl-K A for a right arrow and Ctrl-K I for the infinity. Now I have to use their "new" equation editor with unpredictable behaviour. No hot keys, or useless hotkeys that you basically have to type the entire command to do something you were doing with just two keys. Sometimes the correct maths won't even render unless I press the spacebar a couple of times! It has been a pain in the ass. It took me about 3x keystrokes and 1.5x time to do the same thing that I was doing with the old editors.
It's not exactly the same, but I definitely remember Microsoft releasing some kind of conversion tool around the start of Office 2007's life that could convert the newer XML based files into the older '03 compatible files. Or maybe it was the other way around... No idea if that tools still kicking around somewhere.
Similarly I could live happily ever after with Photoshop 7.x or CS1 if they took full advantage of modern operating systems and hardware.