This excuse is as old as the hills and I've been hearing it since the late 90s, but historically there has been exactly zero training between versions of Office or Windows that changed a lot of the interface overnight. Office workers just kept using them like the rest of the planet.

Not to mention companies who moved on to Google Docs or the web version of Office. Or companies who moved to MacOS 15-10 years ago.

In my state back home the entire workforce moved to LibreOffice and, according to my sister (a government worker), everyone is doing fine. Recently I saw a German government worker using Office to produce a document and she mentioned that she "barely knows how to use it" and "just knows how to load templates, fill and print".

This hypothetical problem of "needs training" only seems to exist when you mention the words "open source".