I knew plenty of office workers managing just fine using OpenOffice 10-15 years ago.

Today people are much more reliant on real-time collaboration, polished cloud and mobile experiences. Fractionalized open source software has a harder time competing with this than file based boxed software workflows of the past.

Agree, Personally I consider these newer systems a curse as far as productivity goes, using a simple email/open-office combination never caused any issues with clients or suppliers in the last 20 years.