Much like iOS/Android & the Web killed MSFTs stranglehold on OSes, google docs & markdown killed MSFT office's stranglehold on office. So many businesses are google doc shops, vast majority of schools are google docs, vast majority of casual document usage is google docs and google docs is open-enough with it's export formats.

Excel at this point is specialist software, like adobe photoshop. Everything else is 'good enough'.

That's being charitable to OSS office packages' UX.

Some wounds are self-inflicted, and open source has a well-known last-20%-polish problem that's especially painful in mass-user scenarios like office software.

OOo wasting the 00s with a circa-90s UI (and Oracle being assholes) is equally responsible for MS Office's continued popularity in enterprise.